Method of Preparation
Prep all ingredients; cut apple into thin slices.
Spread butter on one side of each slice of bread.
Preheat the pan to medium heat. Lay the bread, butter side down into the pan.
On the opposite side, spread the whole grain mustard.
Lay the sliced apple on one side of the bread. Cover with a slice of cheese.
Add the arugula to the other slice of bread.
Top with a slice of cheese and turkey breast.
Fold the sandwich together and continue to cook on both sides until the cheese is melted and golden brown.