Preheat the oven to 400 degrees F (200 degrees C).
Cut each potato in half lengthwise. Place 1/2 tablespoon butter on the cut side of each potato half and season with garlic powder and salt. Close potato halves to form full potatoes and wrap each tightly with a square of aluminum foil.
Bake potatoes directly on the rack of the preheated oven until tender, about 40 to 60 minutes.