Spray a 9 x 7 inch casserole dish with pan spray so the potatoes don't stick to the pan. This also helps with clean-up. Peel and slice the potatoes 1/8 inch thick, place in cold water so they don't oxidize, reserve. Shred the cheese, reserve
Cover the bottom of the casserole dish with a layer of potatoes, overlapping slightly. Sprinkle with diced onion and cover with shredded Gouda cheese.
Sprinkle evenly with flour and season with salt and pepper
Repeat until you have 3 layers of potatoes. Season the top layer but, do not put cheese on the top layer.
Bring cream to a boil and pour over the potatoes. Bake the potatoes in a 400-degree over for 45-60 minutes until the potatoes are fork tender. Remove from the oven and top with more shredded Gouda and parmesan cheese. Re-bake until the cheese melts and turns golden brown, about another 10-minutes. Serve immediately.