Macaroni and Cheese

2 cups elbow macaroni
2 tablespoons butter
2 tablespoons flour
3/4 cup milk
1 cup sour cream or plain yogurt
1/2 cup finely chopped onion
1/2 cup chopped celery
2 cups grated Cheddar cheese


In a medium saucepan, melt the butter. Stir in the flour, then gradually stir in the milk. Heat and stir until thick.
Remove from heat and stir in the sour cream, onion, celery, 1 1/2 cups of the cheese, and the pasta.
Put the mixture in a 2 quart casserole dish. Sprinkle the remaining 1/2 cup cheese over top. Bake at 350 degrees F. for 45 minutes. Makes 4 servings.