Heat the olive oil in a large pan. Add the onion and cook for 5 minutes until softened. Stir in the garlic and cook for a further 30 seconds, then add the tomatoes, the stock and some seasoning. Bring to the boil and leave to simmer for 10-15 minutes.
In a separate pan, cook the tortelloni following the packet instructions. Drain.
Add the asparagus and peas, or broad beans, to the soup and cook for 2 minutes, then stir in the greens, followed by the tortelloni. Simmer for 1-2 minutes more until everything is warmed through. To serve, divide the soup between four bowls and drizzle over some pesto. Top with a little grated cheese, if you like.