Preheat the oven to 350 degrees F (175 degrees C). Grease a 9x13-inch baking dish.
Slice potatoes with skins on into 1/4 inch thick slices. Place potatoes into a large pot and cover with salted water. Bring to a boil over high heat, then reduce heat to medium-low, cover and simmer until tender, 10 to 15 minutes. Drain and allow to steam dry for a minute or two.
Mix together mayonnaise, sour cream, onion powder, garlic powders, seasoned salt, pepper, bacon, onion, and American cheese in a bowl. Stir in potato slices. Pour mixture into prepared baking dish. Sprinkle top with grated Parmesan cheese.
Bake in the preheated oven until bubbly and beginning to brown, 35 to 40 minutes.