In a bowl, combine 1/2 cup softened butter, 1/4 cup parsley, 1/4 tsp of salt, 1/4 tsp of garlic powder and finely minced garlic. Mash together with a fork. In a separate bowl, combine the parmesan and mozzarella cheese.
Cut your loaf of French bread in half lengthwise and spread the butter mixture on the inside of each half. Place bread buttered side down on a large sheet of Reynolds Wrap® Non-Stick Foil and fold over the foil, creating a pack and sealing the edges. Place foil pack on the grill buttered side down, cover the grill with the lid and cook for 5 minutes.
Carefully open the foil. Flip the halves over with tongs and sprinkle the cheese mixture on top. Do not close the foil pack. Cover the grill and continue to cook for another 4 to 5 minutes to melt the cheese. Remove from the grill, slice bread, garnish with parsley and serve warm.