Melt the butter in a skillet.Place bread slices into pan and allow to brown on bottom sides before adding cheese.Add sliced cheese and place one bread over the other.Use a spatula to press down on the sandwich then flip over.Turn heat to low, cover to melt cheese if needed.If cheese isn't melted as much as you'd like, cut sandwich in half and place cut side down onto hot skillet to melt cheese in center.Enjoy immediately!