Combine dry milk powder, flour, and salt in a mixing bowl.
Cut in butter until it resembles coarse crumbs
Place in an airtight container and store in the refrigerator.
To Use: In a saucepan, combine 1/2 cup Cream Sauce Mix with 1 cup water. Cook over medium heat, stirring often until thickened. For Cheese sauce, add 1 cup shredded cheese to thickened sauce and stir until melted.