Ombré Gratin

1. Preheat Oven and Prepare Baking Dish

Preheat your oven to 375 degrees. Grease a 13-by-9-inch baking dish with butter and set it aside.

2. Sauté Shallots and Garlic

In a saucepan, melt 3 tablespoons of unsalted butter over medium heat. Sauté chopped shallots and garlic cloves along with black peppercorns until shallots are translucent.

3. Simmer Cream Mixture

Add half-and-half, bay leaves, thyme leaves, grated nutmeg, and kosher salt to the saucepan. Simmer for 20 minutes, then strain.

4. Temper and Combine Egg Yolks

Whisk the egg yolks in a bowl. Gradually add warm cream to temper them, then whisk back into the cream mixture. Reserve 1 cup of cream for serving.

5. Prepare Red Potato Layer

Toss thinly sliced red potatoes with kosher salt and black pepper, then stir into the cream mixture.

6. Layer Beets and Cheese

Layer sliced beets in the baking dish, season with salt and pepper, and sprinkle 1/3 of Gruyère cheese over them.

7. Add Sweet Potato Layer

Shingle sliced sweet potatoes over beets, season, and add another third of Gruyère cheese.

8. Arrange Butternut Squash Layer

Layer the butternut squash slices, season, and top with the remaining Gruyère cheese.

9. Top with Red Potato Slices

Place red potato slices on top and pour over any remaining cream from the bowl.

10. Bake the Gratin

Bake for 1 hour at 375 degrees on the middle oven rack with a sheet pan underneath to catch drips.

11. Add Phyllo Pastry Topping

Increase oven temperature to 400 degrees. Pat gratin dry, add crumpled phyllo sheets on top, and brush with melted butter. Bake for an additional 30 minutes until golden.

12. Cool and Serve

Let the gratin cool for 20-30 minutes. Reheat the reserved cream, season to taste, and serve with the gratin.