5 c. cooked potatoes, diced

SAUCE:

1 stick butter
1/4 c. flour
2 c. milk
1/2 tsp. salt
2 c. grated Cheddar or American cheese
1 tbsp. prepared mustard

Mix butter, flour and milk to make white sauce. Remove from heat, add salt and cheese. Pour sauce over potatoes. Bake 30 minutes in 350 degree oven.