Heat the oil in a large pan over a medium heat. Add the meatballs and cook for 10 minutes, turning, until brown all over. Remove from the pan and set aside.
Add the onion, garlic and paprika to the pan and cook for 5 minutes, until the onion is soft. Return the meatballs to the pan with the tomatoes, stock, lentils and sachets of sauce and parmesan from the meatball pack. Turn up the heat and boil for 10 minutes. Reduce the heat and simmer, covered, for 20 minutes, until the lentils are tender.
Stir in the parsley, cabbage and courgette, and cook for 10 minutes. Serve with the crème fraîche sprinkled with the extra paprika and a scattering of parsley.