- 1 (9-in) store-bought pie crust
- 1 cup brussels sprouts, trimmed and halved
- 4 strips of bacon, diced
- 1 tablespoon butter
- 1 large onion, thinly sliced
- 1 teaspoon chopped fresh thyme leaves
- ½ cup grated Gruyere cheese
- ¼ cup grated Parmesan cheese
- 3 large eggs
- 1¼ cups heavy cream
- Salt and pepper
- ⅛ teaspoon freshly grated nutmeg
- Heat oven to 400°F. Spread the brussels sprouts out evenly on a sheet tray and drizzle with olive oil. Season liberally with salt and pepper.
- Roast, shaking the pan occasionally, until they are crispy and starting to caramelize (about 15-20 minutes). Remove from oven and allow to cool slightly. Reduce the oven temperature to 375°F.
- Meanwhile, in a sauté pan, crisp the bacon. Remove from pan using a slotted spoon and distribute evenly over the bottom of the pre-baked pie crust. Top with the roasted brussels sprouts.
- To the fat remaining in the pan, add the butter, sliced onions, and thyme and cook, stirring occasionally, until onions are soft and lightly caramelized, about 10 minutes. Scatter the onions over the brussels sprouts in the pie crust and top with the grated cheeses.
- In a large bowl, whisk together the eggs, heavy cream, and nutmeg. Season with salt and pepper and then pour the egg mixture over the other ingredients in the pie shell.
- Bake for 40-45 minutes, or until the custard is set and the top is golden brown. Allow to cool slightly before slicing and serving.