1. Add the onion, green pepper and celery to the cooked macaroni; stir. 2. Add 1/2 of the cheese & stir over low heat until melted. 3. Season & stir in evaporated milk. 4. Spoon into well-greased 8x8x2 baking pan & sprinkle remaining cheese evenly over top. 5. Bake in a preheated oven at 350° for 20 minutes. 6. Let stand for 10 minutes and cut into squares to serve.
