white sauce

Mince two ounces of lean ham, one truffle, and six mushrooms; stir this mixture into a gill of white sauce.

If you add a tablespoonful of chopped parsley to a pint of white sauce, you make parsley sauce.

Egg sauce is made by adding chopped hard boiled eggs to white sauce.

It is easily made the basis of a great many sauces, the name of which depends on preferred addition to the white sauce.

You can use up boiled rice in the same way with white sauce and cheese, or you can merely mix your tomato and rice and bake that.