Crockpot scalloped potatoes

Great recipe, I have used it twice and have not been disappointed, AND it's one of those you can heat up in the microwave the next day and is even better! I would call it more of an au gratin because of the cheese, but it was listed as scalloped.
Also, I halve the recipe for Barry and me and it makes two meals (see "better the next day," above...lol).

Crockpot Scalloped Potatoes
1/2 tsp cream of tartar
1 cup water
8-10 medium potatoes, thinly sliced
half an onion, chopped
salt to taste
pepper to taste
1 cup grated American, or cheddar cheese
10 3/4 oz. can cream of celery, mushroom, or chicken soup
1 tsp paprika
Dissolve cream of tartar in water. Add potatoes and toss together. Drain
Place half of potatoes in slow cooker. Sprinkle with onions, salt, pepper, and half of cheese
Repeat with remaining potatoes and cheese
Spoon soup over the top. Sprinkle with paprika.
Cover. Cook on low 8-10 hrs, or High, 4 hours.

I DID MAKE SOME CHANGES...
1.EVEN THOUGH I HALVED THE REST OF THE RECIPE, I USED THE FULL AMOUNT OF CREAM OF TARTAR AND WATER.
2. I USED 4 GOOD SIZED BAKING POTATOES.
3.I USED PROBABLY MORE THAN THE ORIGINAL AMOUNT OF SHARP CHEDDAR BECAUSE I LIKE CHEESE...THAT'S UP TO YOUR TASTES.
4.I USED THE CREAM OF CELERY SOUP...AGAIN, BECAUSE THAT'S WHAT I LIKE.
5.DIDN'T HAVE PAPRIKA SO I USED SEASONED SALT...I THINK THE PAPRIKA WOULD BE GOOD THOUGH.