Place oil in a large pan, add onion, garlic, potato, carrots, zucchini and cabbage. Cook for 5 minutes until softened.
Add stock and tomatoes and bring to the boil. Reduce heat and simmer for 20 minutes. Add the pasta shells and seasoning. Cook for a further 10 minutes., until pasta is al dente. Divided soup between bowls and top each serving with a tablespoon of Parmesan and pesto.