01 -
Preheat oven to 500°F.
02 -
Combine spinach, ricotta, mozzarella, olive oil, egg yolk, garlic powder, oregano, red pepper flakes, and salt in a large bowl.
03 -
Place dough on a lightly floured surface and divide into 4 even pieces.
04 -
With a rolling pin or your hands, flatten each piece into a 7-inch round on a piece of parchment paper.
05 -
Spread 1/4 of the spinach filling evenly over half of each dough round, leaving a 1-inch border around the edge.
06 -
Brush the edges with the egg wash, fold the other half of the dough over the filling, leaving a 1/2-inch border uncovered, and press edges together to seal.
07 -
With a sharp knife, cut 5 steam vents in the top of each calzone and brush the tops with the remaining egg wash.
08 -
Transfer the calzones onto a parchment-lined baking sheet and bake for 8 minutes. Brush with any remaining egg wash, sprinkle with grated Parmesan, and bake for another 7 minutes.
09 -
Move the calzones to a wire rack and let cool for 5 minutes before serving.