Paste some butter on one side of a slice of bread. Paste some mustard on the other side of the slice of bread.
Add the cheese or a slice of cheese and top with a slice of bologna and some more cheese or another slice of cheese. Finish up with a slice of bread. Paste some more butter on the top of last slice of bread.
Place sandwich on a hot skillet. Press the top a bit to help keep some of the heat within the bread.
Brown on both sides. Remove when cheese starts to melt. Cool before serving.
As an extra step, you can add your favourite relish or chopped vegetables to the grilled cheese sandwich.