Cook the spaghetti according to the packet instructions in boiling, salted water.
Meanwhile, heat a non-stick frying pan and add the pancetta, stirring until golden and starting to crisp.
Add the tomatoes and garlic, stirring for 1-2 minutes until the tomatoes just start to break down.
Drain the pasta, reserving 1 ladle of cooking water. Return the pasta to the saucepan, add the bacon and tomato mixture along with the cooking water. Stir through the rocket and season with salt and pepper.
Divide between four bowls, top with Parmesan, and serve.
