Description
This Cheesy Root Vegetable Gratin is a comforting and elegant dish featuring layers of sweet potatoes, parsnips, and beets baked in a creamy mixture of heavy cream, garlic, and thyme, topped with a golden crust of Parmesan and Gruyere cheeses. Perfect as a flavorful side dish for any meal, it combines the natural sweetness of root vegetables with rich, melted cheese for a hearty and satisfying gratin.
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 (whole milk can be used as alternative)
- 4 ounces grated Parmesan cheese, divided
- 1 ounce shredded Gruyere cheese
Herbs and Seasonings
- 1 tablespoon fresh minced thyme, divided plus more for garnish
- 1 garlic clove, minced
- Salt and pepper, to taste
Instructions
- Preheat and prepare the baking dish: Preheat your oven to 375°F (190°C). Butter a medium-sized gratin or baking dish thoroughly with the softened unsalted butter to prevent sticking and add flavor.
- Slice the vegetables: Using a sharp knife or mandoline, carefully slice the sweet potatoes, parsnips, and beets into thin, even slices about 1/8 to 1/4 inch thick. This ensures even cooking and a beautiful layered appearance.
- Make the cream mixture: In a small bowl, combine 12 tablespoons of the heavy cream with the minced garlic, half of the grated Parmesan cheese, and half of the minced fresh thyme. Season with a pinch of salt and freshly ground black pepper and mix well to blend the flavors.
- Layer the vegetables: Arrange a layer of sweet potato slices on the bottom of the prepared dish, then drizzle some of the cream mixture over the layer. Repeat layering with parsnips, then beets, spreading the cream mixture as you go to coat evenly. Continue layering until all vegetables are used, distributing the cream mixture throughout.
- Add cheese topping and remaining cream: Pour the remaining 2 tablespoons of heavy cream evenly over the top layer. Sprinkle the shredded Gruyere cheese and remaining Parmesan cheese over the gratin. Finish by sprinkling the remaining fresh thyme on top for aromatic flavor.
- Bake the gratin: Cover the dish tightly with aluminum foil and bake in the preheated oven for 45 minutes. Remove the foil and continue baking for an additional 15-20 minutes, or until the top is golden brown and bubbly, and the vegetables are tender when pierced with a fork.
- Rest and garnish: Let the gratin rest for 5-10 minutes after removing it from the oven to set the layers. Garnish with extra fresh thyme leaves before serving for a fresh herbal note.
Notes
- The mix of root vegetables gives a balance of sweetness and earthiness; feel free to add other root vegetables like turnips or rutabagas.
- Using heavy cream thickens the gratin and adds richness, but whole milk can be a lighter substitute, though the texture will be less creamy.
- Slice the vegetables as uniformly as possible to ensure even cooking and a prettier presentation.
- Par-cooking beets before slicing can reduce baking time if preferred, but they do cook fully in the gratin as described.
- This dish can be prepared ahead and refrigerated before baking; just add 5-10 extra minutes to the baking time if chilled.
Keywords: root vegetable gratin, cheesy gratin, sweet potato parsnip beet gratin, creamy vegetable bake, holiday side dish