3 tablespoons butter
3 tablespoons flour
2 1/4 cup milk or half and half
2 garlic cloves, minced
1 cup riced cauliflower
8 ounces shredded chicken
1 cup finely grated Parmesan
8 cooked lasagna noodles
½ cup marinara sauce
Preheat oven to 350 degrees. Butter a large casserole dish and set aside.
Melt butter in a large skillet over medium heat. Add garlic and cauliflower and saute until garlic is fragrant, about 30 seconds. Whisk the flour into the butter and garlic and cook until the mixture is bubbling and golden, 1 minute more. Gradually pour in milk, whisking constantly. Bring mixture to a simmer, then stir in Parmesan. Let simmer until the sauce thickens, about 2 to 3 minutes. Season to taste with salt and pepper.
Spoon a thin layer of sauce onto the bottom of the baking dish.
Lay cooked noodles in a single layer on a cutting board or baking sheet. Spread Alfredo sauce on each noodle, then add chicken. Roll up the lasagna noodle. Lay the roll-ups in the baking dish seam side-down. Mix remaining alfredo sauce with the ½ cup marinara sauce and pour over the top of the roll ups.
Bake for 15-20 minutes, until the sauce is bubbly and beginning to brown.