Brussels Sprouts Gratin Recipe

Preheat the oven to 400 degrees F. Spray an 8×12-inch gratin dish or casserole with olive oil.

Add the brussels sprouts into the dish, then season with salt and pepper.

Spray more olive oil over the Brussels sprouts, then place the dish in the lower third of the oven.

Bake for 15 minutes, toss, then bake for an additional 10 minutes.

Heat a medium nonstick pan over medium heat. Add the butter and let it melt, then add the shallots and cook for 4 to 5 minutes, until softened. 

Sprinkle the flour over the shallots to make a roux, whisking for 1 to 2 minutes. Add the milk, then stir with a wooden spoon until the roux is incorporated into the milk.

Cook over medium-low heat for 4 minutes, stirring, until the sauce thickens.

Add the fresh thyme, parmesan and half of the grated Gruyere cheese into the white sauce, then stir until the cheese is melted and incorporated into the sauce.

Pour the sauce over the brussels sprouts, then top with the remaining cheese.

Bake for 15 minutes until the top is lightly browned and bubbly.

Serve warm, and enjoy!