-
In a small sauce pan, bring milk to a boil, then set aside. In another saucepan, melt butter over low heat. Blend in flour and cook slowly, stirring, until the butter and flour froth together for 2 minutes without browning.
-
Remove pan from heat, and when butter has stopped bubbling, pour in hot milk and beat vigorously with a whisk to blend.
-
Set saucepan over moderately high heat and stir until sauce comes to a boil. Boil for 1 minute, stirring.
-
Remover from heat and add salt, pepper, mustard and cheese. Stir until combined and set aside.