- Preheat the oven to 475°F.
- Shape each ball of dough into a round and arrange on 2 baking sheets. Lay the prosciutto evenly over the dough, tearing it to fit.
- Scatter the cherry tomatoes and mozzarella over the prosciutto, then top with the onions and black olives. Drizzle the olive oil over the pizzas.
- Bake the pizzas until golden brown and bubbling, 10 to 12 minutes.
- Remove from the oven and transfer to plates. Scatter the arugula evenly over the pizzas and serve at once.
NOTE: You can make 1 large pizza in place of 4 individual pizzas. Simply stretch the dough to fill a large rimmed baking sheet, top and bake for about 15 minutes.