Preheat your oven to the highest heat possible.
Form a ball from the pizza dough. Start by making a circular motion with the palm of your hand, with some pressure. Then release the pressure gradually until you get a nice ball shape.
Put your pizza dough balls on a lightly floured work surface. Dust them with some more flour, and let them proof covered with a kitchen towel for another 15 minutes.
Shape your dough to form a large, thin disk and place it in a pizza pan.
Put your tomato purée (passata) on top of your pizza dough, in the middle. With a back of a spoon or a ladle, using circular motions towards the edges, make sure the tomato covers your pizza dough. Leave an edge about 1 inch (2-3 cm) thick.
Drizzle a few drops of extra virgin olive oil and sprinkle some dried oregano and salt.
Add your mozzarella cheese. Just tear it in bite size pieces, and place them over the tomato sauce.
Put your prosciutto slices on your pizza. Make sure to cover it all, except the edges.
Transfer your prosciutto pizza into the oven. Bake for 10 minutes, or until the edges are slightly browned.