Layer 1/3 of the potato slices in the baking dish, slightly overlapping. Season lightly with salt and pepper. Spread 1/3 of the pumpkin sauce over the potatoes, and sprinkle with 1/4 cup each of Cheddar and Gouda. Continuing layering the remaining potatoes, seasoning, sauce, and cheese, for a total of 3 layers.☞ TESTER TIP: Divvy the potatoes into three equal piles so you know how many potatoes you’ll need to fit into each layer.