Place the flour, dried yeast, salt, chopped rosemary, grated Parmesan and 2 tablespoons of the olive oil into a food processor and pulse for 3 seconds. Pour in most of the water and turn on again, mixing till you have soft dough. Add the remaining water if needed to bind the focaccia dough. Turn the dough out onto a floured work surface, and knead the dough till soft for at least 5 minutes. Form into a ball. Grease a large bowl with some of the remaining olive oil and place in the dough. Brush the top with some more oil, cover with cling film, and leave to rise for 45 minutes, or double in size. Turn the dough out onto a floured surface again and knock out the air, flattening the dough. Roll out the focaccia, 1 inch bigger than your baking tray all around. Flour the baking tray, and lift in the dough, pushing into the sides of the tray. Drizzle with little olive oil, sprinkle over a little coarse salt and allow to rise again for 20 minutes. Bake for about 20 minutes at 200`c, or until the focaccia is golden brown and cooked through. Immediately lay over the sliced mozzarella, Parma ham and rocket leaves. Drizzle with extra virgin olive oil and serve.