Preheat the oven to 375° F and center the rack to the center of the oven. Grease an 8x8 baking dish, set aside.
Finely chop the onions and peel the potatoes.
1½ lb Russet Potatoes, ½ medium onion, chopped
Alternate layers starting with sliced potatoes, chopped onions, flour, salt, and pepper. You should have a total of three layers.
4 tablespoon flour, salt to taste, pepper to taste
Sprinkle the cubed butter on the top layer of flour.
3 tablespoon butter,
Heat the milk in the microwave for 1 minute. Pour over the top layer in the baking dish. Top with cheese.
2 cups whole milk, 1 cup shredded gouda cheese
Bake uncovered until potatoes are fork tender, about 50 minutes.
Uncover and bake an additional 15 minutes until the cheese top bubbles and starts to brown.
Broil for 2 minutes if the top needs more browning.
Remove the baking dish from the oven and let rest for 20 minutes for the sauce to thicken. Garnish with chopped parsley and serve.
1 tablespoon chopped parsley