01 -
Preheat oven to 260°C (500°F).
02 -
In a large bowl, combine spinach, ricotta, mozzarella, olive oil, egg yolk, garlic powder, oregano, red pepper flakes, and salt. Mix thoroughly until well incorporated.
03 -
Place dough on a lightly floured surface and divide into 4 equal portions.
04 -
Flatten each piece of dough into a 18cm (7-inch) round on pieces of parchment paper, using either a rolling pin or your hands.
05 -
Spread one-quarter of the spinach filling evenly over half of each dough round, leaving a 2.5cm (1-inch) border around the edge.
06 -
Brush the edges with egg wash, then fold the empty half of dough over the filling, leaving the bottom 1.25cm (½-inch) border uncovered. Press edges together and pinch with fingers to seal completely.
07 -
Using a sharp knife, cut 5 small steam vents in the top of each calzone. Brush tops thoroughly with egg wash.
08 -
Transfer calzones on parchment paper to a baking sheet and bake for 8 minutes.
09 -
Remove calzones from oven, brush with any remaining egg wash and sprinkle with grated Parmesan. Return to oven and bake for an additional 7 minutes until golden brown.
10 -
Transfer to a wire rack and let cool for 5 minutes before serving to allow filling to set.