Cheesy Root Vegetable Gratin
A show-stopping side dish made with layers of sweet potatoes, parsnips, and beets baked in a creamy garlic sauce with cheese, perfect for festive occasions.
Ingredients
Root Vegetables
- 1 tbsp unsalted butter, softened
- 1-2 long sweet potatoes, peeled (about 2 inches thick)
- 3-4 large parsnips, peeled
- 3-5 small beets, peeled
Cream and Cheese
- 14 tbsp heavy cream, divided
- 4 oz grated Parmesan, divided
- 1 tbsp fresh thyme, minced, divided
- 1 clove garlic, minced
- 1 oz shredded gruyère
Seasoning
- Salt and pepper, to taste
Instructions
Preparation
- Preheat oven to 400°F (200°C) and butter a 3-quart baking dish.
- Slice sweet potatoes, parsnips, and beets into very thin rounds.
- Toss sweet potatoes and parsnips with 4 tbsp cream, ½ oz Parmesan, 1 tsp thyme, salt, and pepper.
- Toss beets with 2 tbsp cream, ½ oz Parmesan, 1 tsp thyme, salt, and pepper.
Assembly and Baking
- Pour remaining cream (about ¼ cup) into the baking dish. Add garlic and ½ oz Parmesan.
- Arrange vegetables upright in rows, alternating sweet potato, parsnip, and beet until the dish is full.
- Sprinkle top with salt, pepper, and remaining Parmesan. Cover with foil and bake for 30 minutes.
- Remove foil, sprinkle with gruyère, and bake another 18–20 minutes until fork-tender and bubbly.
- Garnish with fresh thyme and serve warm.
Notes
To prevent beet juice from staining, coat them lightly with cream before layering. A mandoline makes slicing fast and ensures even cooking. Covering the dish at first steams the vegetables; uncovering later crisps the top. Make ahead by assembling the gratin, refrigerating overnight, and baking before serving.