1 (3-pound) head cauliflower, cut into large florets (or 2 lb. frozen bag)
Kosher salt
4 T. butter, divided
3 tablespoons all-purpose flour
2 cups hot milk
freshly ground black pepper to taste
pinch grated nutmeg
3/4 cup freshly grated Gruyere, divided
1/2 cup freshly grated Parmesan
1/2 cup fresh bread crumbs
Preheat the oven to 375 degrees F.
Cook the cauliflower florets in a large pot of boiling salted water for 5 minutes, you want it still firm (not too soft). Drain.
Meanwhile, melt 2 tablespoons of the butter in a medium saucepan over low heat. Add the flour, stirring constantly with a whisk for 2 minutes.
Pour the hot milk into the butter-flour mixture and whisk until it comes to a simmer. Simmer, whisking constantly, for 1 minute, or until thickened. Off the heat, add 1 teaspoon of salt, pepper, nutmeg, 1/2 cup of the Gruyere, and the Parmesan. (If mixture is too thick, add a little more milk.)
Pour 1/3 of the sauce on the bottom of an 8 by 11 by 2-inch baking dish sprayed with Pam. Place the drained cauliflower on top and then spread the rest of the sauce evenly on top.
Combine the bread crumbs with the remaining 1/4 cup of Gruyere and sprinkle on top. Melt the remaining 2 tablespoons of butter and drizzle over the gratin. Sprinkle with salt and pepper.
Bake for 25 to 30 minutes, until the top is browned. Let set up for 10 minutes before serving. Serve hot or at room temperature.
(adapted from Ina Garten)
