2 lbs. potatoes (about 6 med.)
1 sm. onion (thinly sliced)
1/4 c. flour
1 tsp. salt
1/2 tsp. pepper
3 tbsp. butter
1 (10 1/2 oz.) can condensed cream of mushroom soup
1 c. milk
1 (4 oz.) can sliced mushrooms, drained
4 slices process American cheese

Wash and thinly slice unpeeled potatoes. Drain. Put 1/2 of sliced potatoes in greased 2 quart casserole. Top with 1/2 of onion slices, flour, salt and pepper. Add remaining sliced potatoes and onions. Sprinkle with remaining flour. Add butter (in bits), mushroom soup and milk.

Cover and bake in 350 degree oven for 45 minutes. Remove from oven and add mushrooms - stir. Return to oven for 30 minutes, covered. Top with cheese slices and bake 15 more minutes uncovered. Serves 8.