Cauliflower Gratin

Preheat your oven to 375°F (190°C) and grease a 9×13-inch baking dish.

Bring a large pot of water to a boil. Add the cauliflower florets and cook for about 5 minutes until tender but still firm. Drain and set aside.

In a saucepan, melt the butter over medium heat. Add the chopped onion and minced garlic, cooking until softened, about 3 minutes.

Stir in the flour, salt, onion powder, nutmeg, and black pepper. Cook for about 1 minute to form a roux.

Gradually pour in the milk, stirring constantly until the mixture thickens, about 3-4 minutes. Once thickened, remove from heat.

Stir in the sour cream and half of the Gruyère and Parmesan cheeses, continuing to stir until fully melted and smooth.

Place the drained cauliflower florets in the prepared baking dish. Pour the cheese sauce evenly over the cauliflower.

Sprinkle the remaining Gruyère, Parmesan, and breadcrumbs over the top of the gratin.

Bake for 25 minutes, or until the top is golden and bubbly. Remove from the oven and sprinkle with fresh parsley.