Spray a 9 x 13 inch pan with Pam. Shred cheddar and Velveeta cheeses and mix together. Cook macaroni. Drain, do not rinse. Put the macaroni in the prepared pan. Add the cheeses, and mix all together until the cheese melts. Blend in the milk. Top with sliced American cheese. Top with crushed corn flakes. Bake at 350 deg. F. for 1/2 hour.
