Quite a few years ago my brother-in-law made these scalloped potatoes for a family get together, I've been making them every since. It was love at first bite! If you are a bacon and Mozzarella cheese lover, like me, then this is a must try. This is a wonderful dish if company's coming or a great dish for a Pot Luck Supper.
Pre-heat oven to 375 degrees. Grease a 13x9 baking dish.
Spread 1/2 of the chopped bacon on the bottom of the baking dish, top with 1/2 of the sliced potatoes, sprinkle with 1/2 the onion.
Mix together in a small bowl the flour, salt and pepper. Sprinkle 1/2 of this over the potatoes and onions. Sprinkle 1 cup of the cheese over the potatoes. Add the remaining bacon, top with remaining potatoes, add remaining onions, sprinkle with the remaining flour mixture.
In a small bowl, slowly whisk the milk into the soup. Pour this over the top of the casserole. Top with the remaining cup of cheese. Cover loosely with foil, so the cheese doesn't stick to the foil, bake 30 minutes at 375 degrees. Remove foil and continue baking another hour and a half or until potatoes are tender.
Note: I use an extra cup of cheese for the topping, a total of 2 cups sprinkled on top.