2 tablespoons of margarine
1/4 teaspoon of salt
1/4 teaspoon of ground mustard (regular mustard can be used)
2 tablespoons of flour
1/2 cup of shredded cheddar cheese
Melt the margarine in a medium-size saucepan over low heat.
Stir in the flour, mustard and salt. Blend together well.
Add the 1 cup of milk and the shredded cheddar cheese.
Stir continuously until the cheese is completely melted and the sauce is smooth and creamy.
Remove from heat and serve.