Sprinkle roast with salt, pepper and garlic powder. Place in Dutch oven. Place sauerkraut around roast. Sprinkle with caraway seeds. Add onions and butter. Pour 2-3" of apple juice over meat and sauerkraut. Cook, covered on top of stove over Low heat for 2 1/2-3 hours. Sauce: Combine sauce ingredients in small saucepan. Heat over Low heat until hot. Blend well.