Bring a large pot of salted water to a boil for the pasta.
Chop tomatoes into ½-inch pieces, and add them and their juices to a serving bowl.
Season with ½ teaspoon salt and ¼ teaspoon peperoncino. Toss, and let sit while you cook the pasta.
Add the pasta to the boiling water.
Meanwhile, combine the basil, parsley, and garlic in the work bowl of a mini-food processor. Pulse to make a chunky paste.
With the machine running, add the olive oil to make a smooth pesto.
Add to the tomato mixture, and toss.
When the pasta is al dente, remove with a spider to the bowl with the tomatoes, and toss well.
Add the mozzarella and grated Grana Padano, and toss well again.
Season with salt if needed, toss again, and serve.