Toast the bread on both sides in a toaster.

Scramble egg, and pepper in a bowl. Set Aside.

Once Bread is toasted, take it out of the toaster and put the mozzarella cheese in the center. Close the sandwich and dip each side of the sandwich in the egg mixture to get an even coating on the outside of the sandwich bread. Set Aside.

Heat butter in a frying pan, until melted. Add the egg battered sandwich with a lid for 3 mins until the bottom side is golden brown. Then flip it, and cook an additional 3 mins until the bottom side is golden brown and the cheese on the inside is melted.

Remove the sandwich from the frying pan and slice into bite sized pieces.

Heat the Sauce, until hot.

Serve Sandwich slices with the side of sauce to dip in.