Spread a tablespoon of the butter mixture on one side of each bread slice.
4 bread slices
Heat a non-stick skillet on medium heat and place two of the bread slices on the skillet, the buttered side down.
Next, top each bread slice with 2-3 slices of mozzarella cheese. Then top the mozzarella cheese with the rest of bread slices, the buttered side up.
4 slices mozzarella cheese
Cook for 1-2 minutes or until the bread becomes a golden-brown colour. Then carefully flip the sandwich on the other side and cook for 1-2 minutes more.
Turn off the heat and cut the sandwiches into halves then serve immediately.
Notes
Make sure to cover the entire bread surface with the butter mixture. Don't forget the edges.
I recommend cooking this sandwich on medium to low heat to give the cheese time to melt well.
This recipe makes two sandwiches. Feel free to scale it down for one sandwich or scale it up for more than two sandwiches.