Saute' celery, onion, and broccoli in about 4 tablespoons of butter or margarine and chicken broth until tender. Add a little water if needed. (Add salt and pepper if desired.)
Cook down until there is little juice remaining.
Add cheese sauce until it looks right, about 3/4 large can. Add milk as needed.
Cook for a while on low, stirring often. It thickens while simmering.
Can also be put into a crock pot to simmer.