Cheese sauce recipe for multiple dishes?

Melt a spoonful of er over a low heat. Add a spoonful of flour and mix until it goes into a little ball. Take off the heat and GRADUALLY add about 1/4 pint of milk. By gradually, I mean a small splash of milk, then stir until the ball of flour has absorbed the milk. Add another splash and mix again. The mix becomes stickier and thinner until it is like plain milk. If you add the milk too quickly, or don't stir well enough, the mix will go lumpy. Once all the milk is mixed in, put back on the heat and stir until it comes to the boil and thickens slightly. Turn off the heat and add cheese to taste.