Preheat oven to 400F.
Melt 2 tablespoons of butter in a skillet.
Add the flour and whisk over medium-high heat for 1 minute.
Add the milk and the half-and-half; cook, whisking constantly, until thickened, about 5 minutes.
Remove skillet from heat and whisk in the cheese.
Whisk in the thyme, Italian seasoning, salt, pepper, chili powder, and nutmeg; set aside and keep warm.
In a large skillet, bring 1/2 inch of salted water to a boil.
Add the cauliflower florest; cover and cook over high heat for 5 minutes.
Drain the cauliflower in a colander.
Melt remaining butter in a skillet.
Add the onion and cook over medium-high heat for 3 minutes.
Stir in the minced garlic and continue to cook for 1 minute, or until fragrant.
Add the prepared cauliflower florets to the skillet and cook, stirring frequently, for 2 minutes.
Transfer the cauliflower to a 2 quart baking dish and spread the prepared cheese sauce on top.
Sprinkle the top with the chopped almonds and paprika; bake in the oven for 20 minutes, or until bubbling and browned on top.
Let stand for 10 minutes before serving.