Cheddar Mushroom Potatoes

5 Yukon potatoes
1 white onion, sliced thin
1 can Cheddar cheese soup
1 can cream of mushroom soup
1 soup can of milk

Peel and slice potatoes and onions. Layer in a greased casserole dish. Mix soups together and thin with one can of milk. Pour over potatoes. Cover and bake at 350 degrees F. for 1 hour or until done. To turn this dish into a main dish, brown ½ lb. ground beef and add in middle layer.