- 1 head cauliflower, broken into florets
- 1/4 cup butter
- 1/4 cup all-purpose flour
- 1 3/4 cups 1% milk
- 2 ounces Parmesan cheese, grated
- salt and ground black pepper to taste
- 2 ounces mature Cheddar cheese, grated
- Preheat oven to 425 degrees F (220 degrees C).
- Place cauliflower in a large pot and pour in enough water to cover; bring to a boil and cook until tender yet firm to the bite, 8 to 10 minutes. Drain and transfer to a baking dish.
- Melt butter in a small saucepan over low heat. Add flour and mix using a whisk or wooden spoon until smooth and mixture pulls away from the side of the saucepan, 2 to 3 minutes. Pour in milk, a little at a time, and whisk continuously until sauce is thickened but still pourable, 3 to 4 minutes.
- Stir Parmesan cheese into sauce until melted; season with salt and pepper. Pour sauce over all of the cauliflower. Sprinkle Cheddar cheese over the top.
- Bake in the preheated oven until cheese is golden brown, 20 to 25 minutes.