Heat the oil in a pan over a medium heat and gently cook the onion, pepper and carrot for around 5 minutes until starting to brown.
Add the stock and bring to the boil. Then reduce the heat, add the spaghetti and cook for 6-7 minutes
Add the tomatoes, oregano and soya beans and bring back to a gentle boil, stirring regularly.
Check the pasta is cooked, then spoon the soup into bowls. Add a dollop of pesto to each, then sprinkle with ground black pepper and grated Parmigiano cheese.