1 batch thin-crust pizza dough (I used a roll of Pillsbury ready-made thick pizza dough), or 2 lbs store-bought pizza dough
2-3 cups filling: any favorite combination of cooked meat, cooked veggies, and mozzarella cheese (for these, I used ham, frozen chopped spinach, ricotta, and mozzarella)
Preheat oven to 450 degrees. Divide the dough into 6 even pieces and place on parchment paper. Press each piece into a flat disk and roll out until about 8” diameter.
In the bottom third of the circle of each piece, spread about 1/3 cup of filling, leaving about an inch border around the edge. Fold the top part of the dough over the bottom, pressing around the edges of the non-folded edge to seal.
Tap the calzones lightly to spread filling evenly.
Brush the calzones lightly with olive oil and stab tops of the calzones with a fork to allow steam to vent out during cooking.
Bake calzones for 15-20 minutes. Rotate the tray in the oven and bake another 15 minutes, or until golden brown on top and browned on the edges.
Cool briefly and serve with marinara sauce.