Spread butter evenly over one side of each slice of bread.
Preheat a large skillet or griddle over medium-low heat. Place 1 slice of bread buttered side down into hot pan. Top with 4 slices of cheese. Top with 1 slice of bread, buttered side up. Grill for 1-2 minutes or until golden brown.
Flip sandwich using a spatula. Grill an additional 1-2 minutes or until golden brown. Transfer to a plate, cut in half and serve.