Macaroni and Cheese

1-1/2 C elbow macaroni
3 TB butter or margarine
2 C milk
1/2 tsp salt
dash of pepper
1/2 C minced onion (optional)
OR 2 TB dried minced onion
2 C cheddar cheese, shredded

Cook macaroni in boiling, salted water until tender; drain. Melt butter, blend in flour, add milk. Cook and stir until thick. Add salt, pepper, onion, and cheese; stir until cheese is melted. Mix sauce with macaroni. Turn into casserole. Bake at 350 for about 45 minutes or microwave for 7-10 minutes. Serves 6.