Place pizza stone on the center oven rack. Preheat to 450°F (220°C) for one hour to get it really hot. If you do not have a pizza stone, use a baking sheet.
Remove pizza dough from refrigerator and allow to come up to room temperature, about one hour.
Place each dough ball on a lightly floured surface and push down with your hands to form a circle that is about one-quarter inch thick and 8-inches in diameter. If dough shrinks back it is too cold. Allow to warm up for a few more minutes and try again.
Place two dough circles on a parchment paper sheet or leave on floured surface if frying. Add ground meat mixture to one half of the dough circle, keeping at least an inch clear around the edges.
Top with pepperoni slices, if using, or any additional toppings that you would like, and shredded mozzarella cheese.
Fold the top half of the dough over and gently press down until the seam match up. Start to press edge of the dough together to seal until almost all the way around.
Gently press down on the center to remove air pockets. Seal the remaining edges together and flip the edge over a bit to form a rim.
Cut two small slits in the top of the calzone for hot air to escape while baking. Brush top of calzone with beaten egg or olive oil, then sprinkle with grated parmesan cheese and Italian seasoning.
Slide calzone and parchment paper onto hot baking stone, or place parchment lined baking sheet with calzones into preheated oven.
Bake for 15-20 minutes or until golden brown. Remove from oven and allow to cool for 10 minutes before serving.
To Fry Calzone:
Heat oil in a wok or large saucepan to 375°F (190°C).
Slide prepared calzone into the hot oil one at a time, and cook until golden brown. Flip over and cook the second side.
Remove from oil and place on paper towels to drain, and allow to cool for 10 minutes before serving.
To prevent a soggy calzone, make sure to properly drain any moisture-rich ingredients like vegetables or cooked meats before adding them as fillings. It is best to not use fresh mozzarella (the kind in a ball with water) because it releases water as it cooks. The same goes for mushrooms. It is better to sauté them ahead of time.
Make sure not to overfill the calzone, as this can cause the filling to burst out during baking. Leave some space around the edges of the dough when adding the fillings, and seal the calzone tightly to prevent leakage.
Leftovers: Allow the calzones to cool completely. Wrap the cooled calzone tightly in plastic wrap or aluminum foil to help retain moisture and prevent them from drying out. Place the wrapped calzones in an airtight container or resealable plastic bag. Store in the refrigerator for up to 3-4 days. When you’re ready to enjoy the leftover calzones, you can reheat them in a preheated oven at 350°F (175°C) for about 10-15 minutes or until heated through. Alternatively, you can reheat them in the microwave for 1-2 minutes.