Heat oven to 350 degrees (moderate). Arrange 3 to 4 cups thinly sliced or coarsely grated raw potatoes in layers in 1 1/2 quart baking dish. Sprinkle each layer with minced onion (1 tablespoon in all), salt and pepper; dot with butter. Add 1 1/4 cups hot milk. Bake uncovered about 1 1/4 hours. 4 servings.