Root & Tuber Vegetables

Root and tubers vegetables are the underground storage system of various plants found around the globe. They share similar characteristics in texture, starch and fiber. This makes preparation methods quite similar from one starchy vegetable to the next. Potatoes are the most popular tuber vegetable in the US, but interest in other roots and tubers including exotic tropical varieties has created a surge in their use. Mastering classic techniques for potatoes will lead to success in the preparation of other types of tubers and roots. Think of a universal approach for flavor combinations and techniques when using these vegetables.

Because of their varied starch and moisture levels, potatoes are suited for all types of cooking methods. Sweet potatoes, unrelated to the common potato, are suited more for slow, dry-heat cooking that turns the starch into maltose and gives them a sweet flavor. Tropical roots and tubers often contain higher starch levels that may need special preparation steps. Cassava (manioc, yuca) must be peeled to remove cyanide toxins near the surface before cooking. Taro and dasheen also must be cooked before eating to denature the high calcium levels that cause digestive problems when eaten raw. Yams (boniato), similar to but a distinct species separate from American sweet potatoes, are dry and mealy. Most yams found in the US are actually a variety of sweet potato and not a real yam.

Other root and root-like vegetable, including carrots, parsnips, turnips, and celery root, have far less starch but are cooked in similar methods as potatoes providing a chef with greater menu planning options.

Starch & Sugar in Vegetables

Young vegetables in general have higher levels of sugar and lower levels of starch. As vegetables mature the sugar is converted to starch. Roots and tubers that are harvested and stored become starchier and therefore more fibrous. Cooking methods and cooking times should be adjusted to compensate for this disparity. Some vegetables, like mature carrots, may need the addition of sugar to compensate for their lack of sweetness. Experimenting with textures and flavors, while being conscious of basic taste sensations, will yield the best results.

Moist Heat Cooking Methods

Vegetables cooked by moist heat methods are simple in their preparation and presentation. They can be served by tossing with butter or oil, fresh herbs, salt, and seasoning. Moist heat cooking methods are used as a mise en place step for other finishing techniques including roasting and frying.

Steamed & Simmered

Roots and tubers when steamed or simmered can be cooked in their skins, peeled and cooked whole, sliced, diced or tournéed. Cooking vegetables in their skins retains more nutrients and flavor but sometimes is impractical in a production setting. Steamed and simmered potatoes are used for purees, gnocchi, flatbread dough, potato salads, stews, and casseroles.

Best Choice: New potatoes, all-purpose potatoes, red skin, and yellow skin varieties.


  1. Scrub potatoes
  2. Remove eyes, sprouts and green spots.
  3. Peel if desired.
  4. Cook whole or cut into uniform shapes for even cooking.
  5. Submerge in cold water to prevent discoloration.
  6. Start cooking in cold water for even cooking.
  7. Add salt to the water, 1 oz./28 g per 1 g/4 l of water. For par cooked potatoes increase the salt level.
  8. Cook at a simmer to retain the integrity of the potatoes.
  9. Check for tenderness with a fork or skewer, avoid over cooking.
  10. Drain immediately, oven dry if using for purees, toss with butter/ oil and seasoning, or cool for later use.

Pureed, Mashed, Whipped, & Duchesse

Best Choice: Russet, yellow skin potatoes


  1. Cook potatoes by the moist heat method.
  2. Drain and oven dry
  3. Process through a food mill.
  4. Using a mixer with a paddle or by hand gently whip the potatoes.
  5. For whipped/mashed potatoes add milk/cream, butter, and seasoning
  • For Duchesse potatoes add egg yolks, butter, and seasoning.
  • For Pommes Lorette add equal parts pate a choux. Pipe into shapes and deep-fry.

Glazed Vegetables

Glazing can be a done for almost any type of vegetable but is well suited for root vegetables like carrots, parsnips, turnips, and rutabagas. Because each vegetable cooks up differently it is best to glaze them separated and then combine after cooking. When glazing vegetables, the goal is create a reduction of liquid, butter, and sugar that comes together at the exact time the vegetables are tender and perfectly cooked. Since vegetables are made up mostly of water, adding too much liquid will create a boiled vegetable effect. It is better to start with a minimal amount of water and add more as needed. Two different prep techniques can be used depending on kitchen production demands.

Classic Glazed Vegetables


  1. Cut vegetables into uniform shapes.
  2. Combine in a sautoir or braising pan with salt, butter, and sugar.
  3. Add a small amount of water to coat the vegetables. Avoid drowning the vegetables in water because the result will be boiled vegetables rather than glazed.
  4. Begin to heat the vegetables on the stove top and toss to coat with the liquid.
  5. Cover with parchment and allow to cook until tender but not soft. Toss the vegetables periodically. Add more liquid as needed.
  6. If prepared correctly, the liquid in the pan will reduce to a syrup glaze just as the vegetables have finished cooking.
  7. If the liquid is too watery, strain and reduce it separately and then add back to the vegetables.

Glazed Vegetable Production Method

  1. Prepare a simple syrup glaze using equal parts water and sugar heated together to dissolve the sugar.
  2. Cut vegetables into uniform shapes
  3. Cook vegetables in boiling salted water until 75% cooked. The vegetables should still have a slight bite in texture.
  4. Cool in ice water and drain well.
  5. Sauté in batches with butter or oil as needed; add glaze and seasoning to finish.

Gratinée & Casserole

Potatoes cooked en casserole are combined with milk, cream, savory custard, stock or sauces. They are often gratinéed with grated a cheese or bread crumb crust to add color and texture to the finished dish. The potatoes are sliced, either in a raw or par cooked state, and layered in a buttered dish then covered with the liquid prior to baking.

Best Choice: Russets, yellow skin varieties


  1. Scrub and peel potatoes, par cook if desired.
  2. Assemble all ingredients for rapid prepping.
  3. Heat liquids, cream, sauce, stock or custard to speed the cooking process.
  4. Slice potatoes ⅛” thick on a mandolin; hold in water to prevent discoloration.
  5. Dry potatoes thoroughly; excess moisture will affect flavor, seasoning and texture.
  6. Season the potatoes with salt and pepper.
  7. Butter a casserole dish or hotel pan and rub with raw garlic.
  8. Layer the potatoes in the pan.
  9. Pour the hot liquid over the potatoes to just cover the surface.
  10. Cover with buttered parchment and foil.
  11. Bake in a water bath at 325˚F/160˚C until almost tender.
  12. Remove foil and parchment, top with grated breadcrumbs, or grated cheese (Parmesan, Gruyere, or other hard grating cheese).
  13. Return to oven to brown the surface.
  14. Cut and serve immediately.

Production Cooking Method

  1. If not using immediately remove the casserole from the oven before browning the surface and rapidly cool.
  2. Set another hotel pan with a weight on the top of the casserole to compress the layers.
  3. To reheat, remove foil and parchment, top with grated breadcrumbs, or grated cheese (Parmesan, Gruyere, or other hard grating cheese).
  4. Return to oven to re-thermalize and brown the surface.

Pommes Pavé


  1. Square off potatoes, slice on mandolin.
  2. Season with salt and pepper.
  3. Layer tightly, side by side in a pan lined with buttered parchment.
  4. Cover with foil and bake until tender.
  5. Weight down and cool completely.
  6. Remove from pan, cut into squares.
  7. Sauté until browned on all sides.

Dry Heat Cooking Methods

Fried & Sautéed

A common potato preparation that includes classic French to rustic American traditions with many assorted variations provides a hearty accompaniment to roasts, steaks, and egg dishes.

Best Choice: Red skin and yellow skin varieties

Pommes Lyonnaise

Home fries, also called American or Cottage Fries, Lyonnaise, and Sardalaise all are sliced potatoes fried or sautéed in fat. The potatoes are often blanched, either whole or after slicing, before the final pan-cooked step. Some recipes call for caramelized onions and others vary the fats from oil to butter to duck or goose fat. These recipes can be garnished with the addition of garlic, bacon, peppers, mushrooms, spices and fresh herbs. Contemporary twists can be prepared with root vegetables.


  1. Blanch potatoes, either whole or pre-sliced, until about half cooked.
  2. Drain and oven-dry potatoes to remove excess moisture.
  3. Caramelize the sliced onions in sauté pan; remove from pan and reserve.
  4. Add potatoes and sauté stirring occasionally to brown on all sides.
  5. Add the onions to the potatoes and season with salt and pepper
  6. Garnish with chopped parsley

Potato Pancakes & Latkes

Shredded potatoes formed into cakes and fried are known by different cultural names. These preparations can be served as appetizers with smoked salmon, sour cream, caviar, chives, or applesauce. They can also be served as side dishes for breakfast entrees or with steaks, chops and roasts.


  1. Scrub potatoes, peel if desired.
  2. Simmer whole and par cook until half done.
  3. Drain and cool, peel if needed.
  4. Shred potatoes, toss with a little lemon juice to prevent discoloration.Place potatoes in a colander or strainer and squeeze out excess moisture.
  5. Combine with onions, salt, pepper, eggs, flour and parsley.
  6. Check the consistency and seasoning by frying a sample.
  7. If the mixture becomes waterlogged add more flour.
  8. Heat a sauté pan and add oil to cover the pan by about ⅛”.
  9. Spoon the mixture and flatten slightly to create a round pancake.
  10. Brown until crisp on one side and flip to brown the opposite side.
  11. Serve immediately.

Hash Browns & Rӧsti Potatoes

Hash Browns

Hash Browns

Cooked and shredded potatoes are the characteristics of American hash browns and rӧsti potatoes. Hash browns can be either free form or shaped in a small individual cake. Some variations of hash browns are diced or sliced. Rӧsti are large pan-size cakes that are turned out and portioned in wedges when finished. Like other fried potato preparations, they can be varied with different garnishes and the use of different root and tuber vegetables.

Best Choice: Russets


Rӧsti Potatoes

Rӧsti Potatoes

  1. Scrub potatoes, peel if desired.
  2. Simmer in salted water until half cooked.
  3. Drain and dry in oven.
  4. Cool and peel potatoes if needed.
  5. Coarse grate potatoes
  6. Heat a cast iron skillet or sauté pan. Add oil or clarified butter.
  7. Layer the potatoes evenly in the pan. For hash browns make individual portions; for rӧsti make one large cake.
  8. Season with salt and pepper.
  9. Cook until the potatoes are and even golden brown and flip the cake.
  10. Brown the opposite side and cook until crisp on the outside and tender on the inside.
  11. Remove from pan; for the rӧsti cake cut into servings and serve immediately.

Pommes Anna & Galette de Pommes de Terre

These are sautéed variations using sliced and layered potatoes.

Best Choice: Mature reds, yellow skin varieties


Pommes Anna

Pommes Anna

  1. Scrub, peel and clean the potatoes.
  2. Slice on a mandolin no more than ⅛” thick
  3. Butter a sautoir and layer the potatoes in concentric circles. Season and butter each layer.
  4. Cover the potatoes with a butter parchment cartouche, also called a false lid.
  5. Begin cooking on the stove top to brown the bottom layer of the potatoes. Turn the potatoes if desired.
  6. Weigh the potatoes down with another sauté pan or skillet to compress the cake.
  7. Place in a moderately hot oven 400˚F/200˚C and continue to for about 30 minutes or until tender.
  8. Turn out the cake onto a platter and portion into wedges.
  9. Alternately layer the potatoes on a sheet pan and bake directly in a hot oven.

Pommes Frites, Chips & Gaufrettes

Plunging starchy vegetables in hot fats provides crispy textures, a salty bite, and savory mouth feel that immediately appeals to primal taste sensations. Pommes frites is a French export universally popular around the globe. Chips and gaufrettes, thin and crisp variations, are equally popular and can be prepared with any type of root vegetable.  

Best Choice: Russets

Pommes Frites

Deep fried potatoes are best when fried twice. The first is a blanching stage at a temperature of 300-325˚F/150-160˚C to soften their texture. The finishing stage at 350-375˚F/175-190˚C completes the cooking process providing a crisp texture and golden brown color.


  1. Scrub and trim potatoes, peel if desired and cut into uniform julienne shapes on a mandolin.
  2. Soak in cold water until ready for cooking.
  3. When ready to fry, drain the potatoes well and blot dry on paper towels.
  4. Drop into a deep-fryer at 300-325˚F/150-160˚C for a few minutes to soften the potatoes. Spread out on a sheet pan lined with parchment paper.
  5. The potatoes can be kept cooled or frozen until ready for finishing
  6. To finish, drop in a fryer at 350-375˚F/175-190˚C and cook until crisp and golden brown.
  7. Sprinkle with salt and serve immediately

Ultimate Pommes Frites

This method of blanching in acidulated water provides a perfect crisp pommes frites. They key to this blanching technique is the addition of vinegar to the water and maintaining the water temperature at 160˚F/70˚C which prevents the potatoes from falling apart.


  1. Scrub and trim potatoes, peel if desired and cut into uniform julienne shapes on a mandolin.
  2. Soak in cold water until ready for cooking.
  3. Combine water, vinegar, and salt in a large pot. Add the potatoes.
  4. Bring the water to a temperature of 160˚F/70˚C and maintain the temperature until the potatoes are just cooked through, about 10 minutes.
  5. Drain well and spread out on sheet pans lined with parchment paper. The potatoes can be stored in the cooler or frozen until use.
  6. To finish, drop in a fryer at 350-375˚F/175-190˚C and cook until crisp and golden brown.
  7. Sprinkle with salt and serve immediately.

Chips & Gaufrettes

The key to perfect vegetable chips is ultra-fresh oil and the correct frying temperature. Because of the sugar content in vegetables like sweet potatoes maintaining a low fryer temperature averts the chips from getting too dark or bitter tasting.


  1. Scrub, peel and trim vegetables.
  2. Slice on a mandolin 1/16” thick.
  3. Soak in cold water until ready to cook.
  4. Drain vegetables and pat dry
  5. Deep fry at 300-325˚F/150-160˚C until crisp

Baked & Roasted

To bake and to roast are different names for the same process. The terms are assigned based on traditioal use and to create menu variety and interest.

Best Choice: Russets


Baking is a simple yet delicious method for cooking potatoes. This method can also be used for any type of root vegetable cooked whole in their skin.


  1. Scrub potatoes; pierce them lightly with a fork a few times.
  2. Brush with oil if desired.
  3. Sprinkle a generous even layer of salt on a parchment lined sheet pan.
  4. Place potatoes on sheet pan.
  5. Roast potatoes at 350 until soft
  6. Serve immediately or hold warm for service

Twice-Baked Potatoes

A hybrid technique of baked and pureed potato preparation techniques


  1. Roast potatoes, allow the potatoes to cool.
  2. Slice the top of the potato off lengthwise.
  3. Carefully scoop out the insides leaving about ¼ inch of potato on the skin.
  4. Puree the potatoes using standard puree technique substitute sour cream for milk. Add other garnishes as desired cheddar cheese, bacon, chives, etc.
  5. Place in a pastry bag and pipe into potato shells
  6. Garnish with parmesan cheese, paprika or other topping.
  7. Bake in a moderate oven 350 until hot.


Roasting is a versatile method for cooking almost any type of root vegetable. Roasting concentrates the flavor and creates a pleasing crisp texture through the Maillard browning process that develops the natural sugars in the vegetables. Blanch the vegetables to speed the roasting process.

Best Choice: Russets, new potatoes, red skin, yellow skin varieties


  1. Scrub potatoes or root vegetables and peel if desired.
  2. Cut vegetables into uniform shapes.
  3. Blanch vegetables in salted water if desired.
  4. Toss with seasoning and coat with oil.
  5. Roast in a moderately high oven 400- 425˚F/200-218˚C until tender and brown.

Oven-Roasted Vegetable Chips

Healthy alternatives to deep-fried chips are simple preparations made with any variety of root or tuber vegetable.


  1. Scrub and peel vegetables.
  2. Slice on a mandolin not more than ⅛” thick
  3. Lay out the vegetables on a lightly oiled parchment-lined sheet pan.
  4. Season with salt, pepper or other spics and brush the tops with oil.
  5. Roast in the convection oven at 275˚F/135˚C for about 30 minutes until crisp rotating the pan half way through the cooking process.


All types of roots and tubers can be cooked by the grilling process. Because of the sugar content in some vegetables including sweet potatoes and carrots, par cooking before grilling can speed the process.


  1. Scrub and peel vegetables.
  2. Cut into ¼ “slices, wedges or other shapes. For new potatoes or other small roots split in half.
  3. Season and oil the vegetables. Add additional herbs and spices if desired.
  4. Grill on indirect heat turning to score the vegetables with cross-hatched markings.