1Preheat oven to 425 degrees F (220 degrees C). Grease a 9x13-inch baking dish.
2Arrange one layer of potatoes in the bottom of the prepared baking dish. Sprinkle the potatoes with salt and pepper, 3 tablespoons flour, and 2 tablespoons butter. Repeat layering 2 more times, until all of potatoes have been used. Slowly pour milk over the potatoes until the dish is 3/4 full of milk.
3Bake until the milk comes to a boil (check after 15 minutes), then reduce heat to 375 degrees F (190 degrees C) and bake until potatoes are tender, 45 to 60 minutes more.
Footnotes
Tip
Aluminum foil can be used to keep food moist, cook it evenly, and make clean-up easier.