In a small bowl, mix together spinach, cream cheese, Parmesan, pepper, and salt.
Unroll pizza dough and roll out on a floured surface until it is desired thickness, thin enough to make 8 - 5-inch squares.
Cut dough into 8 5-inch squares and put about 2-3 tablespoon of spinach mixture on one side of each dough square.
Fold dough over and pinch all sides together.
Place each calzone on a baking sheet and lightly brush milk over top of each calzone.
Bake for about 10 -15 minutes or until calzones are lightly browned. Serve with spaghetti sauce if desired (I served with vodka sauce and it was delicious).
Notes
Spaghetti sauce is not included in nutrition calculation.