1. Cook penne until al dente. Drain and set aside.
2. Heat olive oil in a large pan on a medium heat. Add garlic and cook for 30 seconds.
3. Bring the stock to the boil and add the diced chicken. Cook for 10 minutes, or until chicken is cooked through.
4. Add passata and heat for 5 minutes.
5. Add cooked pasta to the pan and heat through.
6. Season with salt and pepper, add parsley to garnish and serve with cherry tomatoes and grated Parmesan cheese.