Scalloped Potatoes with Cheese

6 medium potatoes, peel, slice thin
1 small onion, slice thin
1/4 c flour
1 tsp. salt
1/4 tsp. pepper
2 tsp. butter
1 can cream of mushroom soup. or celery soup, or potato soup.
4 slices American cheese
1 cup water
1/2 tsp. cream of tartar

In bowl, put potatoes, water & cream of tartar. Let set about 15 minutes & then drain.

Lightly butter crockpot

Layer 1/2 potatoes

1/2 onions

1/2 flour