Cook the cauliflower. Bring a pot of salted water to a boil. Once boiling, place a steamer basket or insert and add the cauliflower florets. Cover and steam until the cauliflower is tender, about 3-5 minutes. (Do not overcook or it will get mushed after baking in the casserole!) Rinse under cold water to stop cooking. Reserve.
Preheat the oven to 375 degrees F.
Prepare the sauce. In a large saucepan, over medium heat, cook the butter until it melts. Add the garlic and sauté quickly, so it gets fragrant, without letting it brown. Add the flour and whisk, making a roux. Cook for about a minute, letting the roux thicken and darken a bit in color. Carefully and slowly pour the warm milk, whisking constantly until it thickens and starts to bubble.
Lower the heat and season with salt, pepper, nutmeg and paprika. Then, add the cream cheese and cook, stirring, until the cream cheese melts and incorporates.
Remove from heat and add the heavy cream and 1 cup parmesan, stirring with a spoon until smooth.
Assemble the gratin. Add about a 1/4 of the sauce to the bottom of a 8 x 11 inch baking dish. Follow with the steamed cauliflower and crumbled bacon. Top with the cheesy béchamel sauce and finish by sprinkling the remaining parmesan cheese and breadcrumbs.
Bake for 25-30 minutes, until golden brown and bubbly. If desired, you can finish it under the broiler to really crisp it up.
Serve hot!
