Quick and Easy Au Gratin Potatoes

I was in a pinch the other night and wanted to make Au Gratin Potatoes but didn't want to bake them for over an hour, so here goes!

4 large potatoes sliced thin
1 1/2 cup cheddar cheese
1/4 onion minced
3/4 cup milk
4T butter into 4 pieces
8 slices American Cheese

Heat oven to 400*, in a large stock pot boil water enough water to cover potatoes, place potatoes in pot and boil for 10 minutes.
Spray a 9x9 safe pan with non-stick. Layer cheddar cheese, boiled potatoes, milk, onion, butter and American cheese.
** add black pepper if you wish before putting on American cheese.
Cover with aluminum foil and bake for 25 minutes, uncover and bake for 5 more. The dish should be bubbling and browning on the sides.
Serve and enjoy!!