White sauce is a combination of vegetable or chicken broth with white roux. Bechamel is a white sauce made with milk and white roux.
1/2 cup of the liquid combines with a 2 tablespoon butter 1 tablespoon flour roux. This would be good for a couple of people.
You can put in a small amount of meat extract (like better than boullion) mixed into a bechamel sauce to add flavor and color.
Or you can add shredded cheese to a bechamel and then you have the cheese sauce to ladle over macaroni.
All white sauces can have a drop or two of vinegar at the end - try it and see if you like it.