Cook macaroni according to package directions; drain. Meanwhile, for cheese sauce, in a large saucepan, melt butter over medium heat. Stir in flour and pepper. Add milk all at once. Cook and stir until slightly thickened and bubbly. Add cheese, stirring until melted. Stir macaroni into cheese sauce in saucepan, stirring to coat. Cook over low heat for 2 to 3 minutes or until heated through, stirring frequently. Let stand for 10 minutes before serving. Makes 4 servings.