Generously butter the outside of each piece of bread. Assemble 2 slices of cheese with sliced avocado.
Heat a non-stick pan, add the sandwich, and cook each side of the bread until it's golden brown. Slice and enjoy!
Tip: If you cut into it and the cheese isnt melted, just add it back to the pan and add about a teaspoon of water and cover the pan. In 30 seconds to a minute you should have ooey gooey melted cheese!