2) In a large nonstick frying pan over a medium heat, add the prosciutto and cook until crisp. Remove from the pan to a plate and set aside.
3) Season the aubergine with salt and pepper. Add the olive oil to the pan over a medium heat and saute the aubergine for 5 to 6 minutes. Add the garlic and the chilli flakes. Saute 2 to 3 minutes more, being careful not to burn the garlic.
4) Add the tomatoes and season with salt and pepper, to taste. Let the sauce reduce until all the extra liquid is gone, 6 to 8 minutes. Remove from the heat and allow to cool.
5) In a small bowl, combine the ricotta, 1 egg, the Parmesan, pine nuts, 1 tsp of salt and 1 tsp of pepper, the parsley and the basil. Gently combine the ricotta mixture with the aubergine.
6) Break the remaining egg Into a small bowl and add 1 tsp water. Beat well to make an egg wash.
7) Knead the dough a few times on the floured surface and add in the oregano and rosemary. Cut the dough in half and roll 1 piece into an oval about 35cm long and 20cm wide.
8) Put the dough on a pizza peel sprinkled with cornmeal and add half of the ricotta/aubergine mixture half way down the oval, leaving 5cm on each side. Top with 3 slices of the mozzarella and sprinkle with half of the prosciutto.
9) Fold the dough over and roll the edge closed. Brush with the egg wash, sprinkle with a pinch of salt and slide off the peel onto the hot pizza stone in the oven.
10) Repeat with the other half of the dough and ingredients. Bake both calzone for 15 to 18 minutes or until golden brown. Remove from the oven and leave to sit for 5 to 10 minutes. Serve hot!