Name: Chestnut Celery Root Mash
Prep time: 15 min
Cook time: 20 min
Total time: 35 min
Yield: 4-6
Ingredients: 2 medium celery roots, peeled and roughly cubed (the pieces should be about 2 inches in size, and you should have about 1½ pounds of prepared celery root); 4 garlic cloves, peeled; 2 sprigs fresh thyme, plus extra for garnish; 3 cups whole milk (or enough to cover the celery root in the pan); 4 ounces roast chestnuts (vacuum-packed or canned), roughly chopped; 2 tablespoons unsalted butter, divided; 1 tablespoon lemon juice; 1 tablespoon dijon mustard; ½ teaspoon fine sea salt; ¼ teaspoon white pepper; ¼ teaspoon ground sage

Sides

Chestnut Celery Root Mash

Author: Mary DiSomma

When I want a holiday side dish that’s both cozy and unique, I turn to celery root. When you mash it, it has the same comforting texture as mashed potatoes but without totally sticking to your ribs. Paired with chestnuts, the flavor is just wonderful. This easy vegetable side dish is earthy, nutty, and very easy to make. I love serving it with roasted meats or pairing it with braised mushrooms for a vegetarian option.

Cooking with chestnuts this time of year is so special—they add a subtle sweetness and depth that feels very elegant for the holidays. This vegetarian recipe works beautifully as a Thanksgiving side, a Christmas side dish, or at any gathering where you want some winter comfort food. I’ll talk more about this in the tip section below, but the leftover cooking milk makes a fantastic béchamel sauce, too!

Ingredient Tips

Celery root (also called celeriac) is a knobby-looking root vegetable that comes from a special variety of celery that’s grown specifically for its bulb, rather than the stalks you usually see in the supermarket. Even though it might look intimidating at first glance, the pale, tender flesh inside cooks down beautifully. Celery root is a popular ingredient in French and Mediterranean cooking. It’s great in soups, purees, sautés, and holiday recipes like this one.

Believe it or not, this is kind of a complicated question. Let me start by saying that—true to their name—chestnuts are indeed nuts. But nuts are actually fruits. If that’s throwing you off, don’t worry, I literally just learned it myself! Let me break it down.

In botanical terms, a nut is a dry, one-seeded fruit with a hard shell and a protective husk. Chestnuts, hazelnuts, pecans, and walnuts all fall into that category. In all of these cases, the tender inner seed is the part we eat. Peanuts and almonds don’t quite fit the definition of a nut. Peanuts are technically legumes, and almonds come from a fleshy fruit (kind of like a plum).

No matter how they’re classified, chestnuts are really yummy! They blend perfectly into mashes, purées, and other comfort food recipes. Their mild flavor adds warmth without overpowering other ingredients.

One of celery root’s benefits is that it’s lower in calories and carbohydrates than potatoes. It’s also high in fiber and vitamin C. If you want the creamy comfort of mashed potatoes with a lighter nutritional profile, celery root is a fantastic swap! This is one of my favorite celery root recipes to use instead of potatoes.

Despite its very rustic appearance, celery root has a mild, delicate flavor. It tastes like a cross between celery and parsley with a subtle nuttiness. After cooking, it almost melts in your mouth, which is why it blends so well with chestnuts in this dish.

Preparation + Preservation Tips

Celery root needs a little prep work, but don’t worry! It’s easy. Here’s how. First, use a sharp chef’s knife to slice off the top and bottom so it sits flat. Stand it upright and slice downward along the curves to remove the thick, rough peel. Cut into pieces according to your recipe. As soon as you cut it, drop the pieces into a bowl of water with a splash of lemon juice to prevent browning. Celery root oxidizes quickly so this step really makes a difference!

Extra Tips

The milk you use to simmer the celery root is going to absorb a lot of flavor: garlic, thyme, natural sweetness from the vegetable... Instead of discarding it, save it! You can use it for simple béchamel sauces, a creamy pasta sauce, a soup base, or reheating your leftover mash (if there is any)! It will keep for about 2 days in the refrigerator.

Like I said earlier, celery root pairs beautifully with roasted meats (like chicken, turkey, pork, or beef) and mushrooms. You might have guessed that it goes well with nutty ingredients like chestnuts. Herbs and spices that work with celery root include sage, thyme, rosemary, and nutmeg—and you really can’t go wrong with a splash of heavy cream or a pat of butter. I personally like it with salmon! Here are some more ideas to play with too:

Easy Brown Sugar Glazed Salmon in the Oven➝

Mary’s Cheesy Potato Casserole with Crunchy Corn Flakes Topping➝

Mary’s Classic Croque Monsieur Sandwich➝

Wintry Gluten-free White Bean and Ham Soup➝