In a large skillet, melt the butter and saute the onion and garlic in the melted butter until the onions are softened.
Add the flour and spices, and continue cooking and stirring another 2-3 minutes.
Slowly add the half-and-half, stirring until blended. Bring the mixture to a boil. Continue cooking and stirring until blended and thickened, another 5-8 minutes.
Add in the spinach and parmesan cheese. You could cook it in the pan and serve immediately at this point, or transfer it to a casserole dish and refrigerate until later.
When you’re ready to serve, heat the casserole at 350 degrees for about 25 minutes or until heated through.
