Vincente's Macaroni and Cheese
Ingredients:
-
1 (8 ounce) box elbow macaroni
-
1 tablespoon butter
-
1 small onion, chopped
-
2 tablespoons all-purpose flour
-
1 teaspoon dry mustard
-
¼ teaspoon salt
-
1 cup milk
-
1 ½ cups grated sharp Cheddar cheese
-
1 pinch ground black pepper