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Root Vegetable Gratin

Root Vegetable Gratin

This vertically layered Root Vegetable Gratin, featuring vegetables in vibrant autumnal shades, is a noteworthy and unforgettable side dish
Course Side Dish
Cuisine Vegetarian
Keyword butternut squash, potato gratin, root vegetable gratin
Prep Time 30 minutes
Cook Time 1 hour 30 minutes
Total Time 2 hours
Servings 6
Calories 540 kcal
Author Denisse


  • 3 ounces finely grated Gruy√®re
  • 2 ounces finely grated Parmigiano-Reggiano
  • 2 cups heavy cream
  • 2 medium cloves garlic minced
  • 1 tablespoon fresh thyme leaves roughly chopped (plus more for garnish)
  • Salt and black pepper
  • 4 pounds assorted root vegetables such as yams purple sweet potatoes and parsnips, peeled and sliced 1/8-inch thick on a mandoline
  • 1/2 pound butternut squash neck only, peeled and sliced 1/8-inch thick on a mandoline
  • 2 tablespoons unsalted butter


  1. Heat oven to 400 degrees. Combine cheeses in a large bowl. Transfer 1/3 of cheese mixture to a separate small bowl and set aside. Add cream, garlic and thyme to the large bowl with cheeses. Season generously with salt and pepper.
  2. Grease a 2-quart casserole dish with butter. Working in batches, pick up a stack of each type of vegetable about 2-3 inches thick and slices and toss in the cream mixture until every slice is well coated. Neatly stack and lay in the casserole dish with the edges aligned vertically. Continue placing vegetables in the dish, working around the perimeter and into the center until the dish is packed tightly. Pour remaining cream mixture evenly over the vegetables just until the mixture comes halfway up the sides of the casserole, and discard any that remains.
  3. Cover dish tightly with foil and transfer to the oven. Bake for 30 minutes. Remove foil and continue baking until the top is pale golden brown, about 30 minutes longer. Remove from oven, sprinkle with remaining cheese, and return to oven. Bake until deep golden brown and crisp on top, about 30 minutes longer. Remove from oven, let rest for a few minutes, top with fresh thyme and serve.

Recipe Notes

Special Equipment: Mandoline