Garlic Cauliflower Gratin

Directions

1. Preheat oven to 375F° and butter a medium, 2 quart casserole or baking dish.
2. In a large pot of boiling salted water, cook cauliflower for 3 minutes. Use a slotted spoon to transfer to a bowl of ice water to cool. Let sit for several minutes until cool.
3. Drain, then lay cauliflower out on a sheet pan lined with paper towels and let dry completely.
4. In a large saucepan over medium heat, melt the butter.
5. Whisk in flour and cook until golden and starts to bubble, about 1 minute more.
6. Slowly add the milk, whisking until smooth then add the creamy garlic sauce. Continue whisking until the mixture comes to a simmer.
7. Cook, over medium heat, until slightly thickened, about 2-3 minutes.
8. Turn off heat and while stirring, slowly add half of the gruyère, all the parmesan and thyme. Stir until cheese has melted, then season with salt and pepper. The sauce will be thick.
9. Add about half the cauliflower to prepared baking dish, top with half of the sauce mixture.
10. Repeat with remaining cauliflower and sauce, then top with remaining half of gruyère.
11. Bake until bubbly and golden on top, about 25 minutes. If needed, run under the broiler to further brown the top. Serve hot.