Put mozzarella and cream cheese in a microwavable bowl, and microwave for one minute.
Stir and replace in microwave at 30 second intervals until thoroughly melted, stirring well.
Stir in beaten egg and flour.
Dampen hands with water, and knead dough.
Spread dough between two sheets of parchment paper using a rolling pin, aiming for a oval/circle. Remove top parchment sheet.
Fill dough with sauce and toppings of your choice on on half of circle.
Grab the edge of the parchment paper and fold the calzone dough in half, then peel back the top layer.
Dampen your hands and crease the edges of the dough. Smooth out any tears that may have formed with your damp hands.
Brush your calzone with olive olive and cut several steam slots on top.
Bake at 425° for 22 to 25 minutes, or until the top is golden brown.
Let cool. Slice and serve with sauce for dipping.