Method

1. 01

   Preheat oven to 400°F.

2. 02

   Bring a large pot of salted water to a boil. Cut the cauliflower into bite-sized florets and add to the pot. Boil for 5 minutes until just tender-crisp, then drain well and transfer to a 9-by-13-inch baking dish.

3. 03

   In a medium saucepan, melt butter over medium heat. Whisk in flour to form a paste and cook, stirring constantly, for 1 minute until it smells toasty.

4. 04

   Slowly pour in milk while whisking constantly to avoid lumps. Continue whisking over medium heat for 5 to 7 minutes until the sauce thickens enough to coat the back of a spoon.

5. 05

   Remove from heat. Stir in Gruyère cheese until melted and smooth. Season with 3/4 teaspoon salt, 1/4 teaspoon black pepper, and a pinch of nutmeg.

6. 06

   Pour the cheese sauce over the cauliflower and stir gently to coat. Spread evenly in the baking dish.

7. 07

   Bake for 20 to 25 minutes until the top is golden and bubbling at the edges. Let rest for 2 minutes before serving.