Melt butter, put in onion (I puréed mine), cook until soft and caramel colored, add flour to make a roux. Add diced tomatoes and a little chicken stock. Season with salt, pepper, basil, garlic powder and red pepper flakes. I added a chicken bouillon cube for more flavor. Cook for 30 min and then add some half/half and a drizzle of honey. Season to taste. Serve with grilled cheese soldiers for dipping.