Heat a medium skillet over medium-high heat.
In a small bowl, mix the butter, garlic powder and parsley. Lay bread slices out on a surface and spread butter on the tops of the slices. Flip the bread over and top 4 pieces of bread with cheese. Top with other pieces of bread, butter-side up.
Place the sandwiches in the hot skillet and cook for 2-3 minutes on each side, until golden brown and the cheese has melted.