Description
A creamy and cheesy root vegetable gratin featuring sweet potatoes, parsnips, and beets layered and baked with Parmesan and Gruyere cheeses, fresh thyme, and garlic for a comforting and elegant side dish.
Ingredients
Scale
Vegetables
- 1-2 long sweet potatoes (about 2 inches thick), peeled
- 3-4 large parsnips, ends trimmed and peeled
- 3-5 small beets, peeled
Dairy and Cheese
- 1 tablespoon unsalted butter, softened
- 14 tablespoons heavy cream, divided
- 4 ounces grated Parmesan, divided
- 1 ounce shredded Gruyere
Herbs and Seasoning
- 1 tablespoon fresh minced thyme, divided plus more for garnish
- 1 garlic clove, minced
- Salt and pepper to taste
Instructions
- Preheat and prepare dish: Preheat the oven to 400˚F. Grease a 3 quart baking dish with 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 and transfer each vegetable to a separate bowl.
- Coat vegetables: Pour 4 tablespoons heavy cream over each bowl of sweet potatoes and parsnips, and 2 tablespoons cream over the beets. Add ½ ounce grated Parmesan and 1 teaspoon minced thyme to each bowl, then season generously with salt and pepper. Toss gently until all slices are well coated.
- Prepare baking dish base: Pour the remaining ¼ cup heavy cream into the bottom of the prepared baking dish. Sprinkle with ½ ounce grated Parmesan and the minced garlic for flavor layers at the base.
- Assemble gratin: Arrange the sliced vegetables standing up on a bias in rows inside the baking dish starting with sweet potatoes at the top, followed by parsnips, then beets. Repeat this pattern until you have created six rows of root vegetables, layering them attractively.
- Season and cover: Sprinkle the top of the assembled gratin with salt, pepper, and the remaining grated Parmesan. Cover the dish tightly with foil.
- Bake covered: Place the covered gratin in the oven and bake for 30 minutes, or until the vegetables begin to soften.
- Add cheese and uncover: Remove the foil, sprinkle the shredded Gruyere cheese evenly on top, and return the gratin to the oven uncovered.
- Finish baking: Bake for an additional 20 minutes, until the vegetables are fork tender, the Gruyere has melted, and the top has lightly browned.
- Garnish and serve: Sprinkle fresh thyme leaves on top for garnish and serve warm as a comforting side dish.
Notes
- This recipe makes one 3-quart casserole suitable for 8 servings.
- Nutrition estimates are based on the lowest quantity of vegetables used.
- You can prepare the gratin up to one day in advance, refrigerating it tightly wrapped in foil. When ready to bake, increase baking time by 5 to 7 minutes covered.
- Be aware that prepping ahead can cause beet color bleed in the cream, which will not affect flavor but may alter appearance.
- To minimize beet bleeding, coat beet slices lightly with cream and ensure the baking dish bottom is covered with a thin layer of cream and Parmesan.
- The exact amount of cream may vary slightly based on the size of your baking dish; adjust accordingly for surface coverage.
Nutrition
- Serving Size: 1 serving
- Calories: 320 kcal
- Sugar: 6 g
- Sodium: 350 mg
- Fat: 22 g
- Saturated Fat: 13 g
- Unsaturated Fat: 7 g
- Trans Fat: 0 g
- Carbohydrates: 20 g
- Fiber: 4 g
- Protein: 10 g
- Cholesterol: 65 mg
