My work makes these things all the time, so instead of me just buying them at work again and again and spending all my cash, I managed to get the list of ingredients from my co-worker who makes them and am trying to make them for the first time. I don't know the measurements for it, but am guessing by look.
You start by making pizza dough. I normally use my bread maker on the (pasta/dough) function to make the dough for me. Makes it all a little easier in the end.
For the filling, you will need;
A bag of fresh spinach
Black pepper (to taste)
Feta cheese (Same amount as Mozzarella)
Mozzarella cheese (same amount as Feta)
A touch of bread crumbs
Now cut or grate the cheeses up as small as possible. This will help make sure there is even cheese in every calzone and is easier to mix.
Cut the spinach leaves up small as well and then mix together with cheeses. Add the bread crumbs and pepper and put aside until dough is done.
Roll out the dough and then cut into squares. Not too big or too small. The square should be about the size of your hand I would say. Now in the middle of each place some of the spinach filling, then fold the dough over filling and pinch the two sides of the dough together, sealing the filling inside. Cut three slits on the top of each calzone to help let out steam. Then put on a baking sheet (would cover baking sheet with parchment paper, or if you don't have that, aluminum foil) and bake them for 15 minutes at 400'F
Will let you all know how mine came out once they're done.