Description
A comforting and creamy Cheesy Root Vegetable Gratin featuring thinly sliced sweet potatoes, parsnips, and beets baked in a rich blend of cream, Parmesan, and Gruyere cheese, flavored with fresh thyme and garlic for a delicious vegetarian side or main dish.
Ingredients
Scale
Vegetables
- 2 long sweet potatoes (about 2 inches thick), peeled
- 4 large parsnips, ends trimmed and peeled
- 5 small beets, peeled
Dairy and Seasonings
- 1 tablespoon unsalted butter softened
- 14 tablespoons heavy cream, divided
- 4 ounces grated Parmesan, divided
- 1 ounce shredded Gruyere cheese
- 1 tablespoon fresh minced thyme, divided plus more for garnish
- 1 garlic clove, minced
- Salt and pepper to taste
Instructions
- Preheat and Prepare: Preheat the oven to 400°F. Grease a 3-quart baking dish with the softened butter to prevent sticking and add flavor.
- Slice Vegetables: Using a mandoline or sharp knife, slice the sweet potatoes, parsnips, and beets into very thin rounds. Transfer each vegetable type into separate bowls to prepare for seasoning.
- Coat Vegetables: Pour 4 tablespoons of heavy cream over the sweet potatoes and parsnips each, and 2 tablespoons of cream over the beets. Add half an ounce of grated Parmesan and 1 teaspoon of minced thyme to each bowl. Season each with salt and pepper generously and toss well to coat all slices evenly.
- Prepare Baking Dish: Pour the remaining 1/4 cup (4 tablespoons) of cream into the bottom of the baking dish. Sprinkle with half an ounce of grated Parmesan and the minced garlic to infuse flavor into the base.
- Arrange Vegetables: Starting with a stack of sweet potato slices, stand them on a bias along the top edge of the baking dish. Follow with a row of parsnips and then a row of beets. Repeat the layering in this sequence until all vegetables are used, creating six rows of colorful root vegetables.
- Season and Cover: Season the top of the arranged gratin with salt, pepper, and the remaining Parmesan cheese. Cover the baking dish tightly with foil to retain moisture during cooking.
- Bake Covered: Place the covered gratin in the preheated oven and bake for 30 minutes, or until the vegetables start to soften.
- Uncover and Add Cheese: Remove the foil and sprinkle the shredded Gruyere evenly over the gratin. Return the dish to the oven uncovered.
- Finish Baking: Bake for an additional 20 minutes or until the vegetables are fork-tender, the cheese has melted, and the top turns lightly browned and bubbly.
- Garnish and Serve: Remove from the oven and sprinkle with fresh thyme leaves for garnish. Let rest a few minutes before serving warm.
Notes
- Makes one 3-quart casserole dish, suitable for 8 servings.
- You can prepare the gratin up to one day in advance and refrigerate it tightly wrapped in foil. When ready to bake, add 5-7 extra minutes to the covered baking time.
- Beets may bleed color into the cream if prepped ahead, which affects appearance, not taste.
- Ensure beets are just lightly coated with cream to prevent drying during baking.
- The amount of cream used for the base can be adjusted slightly depending on baking dish size; aim for a thin evenly coated bottom layer.
- Using a mandoline makes slicing thin rounds easier and more uniform for even cooking.
Nutrition
- Serving Size: 1 serving
- Calories: 280 kcal
- Sugar: 6 g
- Sodium: 320 mg
- Fat: 18 g
- Saturated Fat: 10 g
- Unsaturated Fat: 6 g
- Trans Fat: 0 g
- Carbohydrates: 20 g
- Fiber: 4 g
- Protein: 8 g
- Cholesterol: 50 mg
