In a large saucepan, heat the olive oil over low to medium heat. Add the chopped onions, carrots, and celery. Cook gently for about 20 minutes, stirring occasionally, until the vegetables are soft. If they start to stick, just add a little water.
Add the sugar, crushed garlic, tomato purée, bay leaves, thyme, and chopped courgettes to the pan. Continue cooking for another 4-5 minutes over medium heat until the vegetables are slightly browned.
Pour in the butter beans, chopped tomatoes, and vegetable stock. Bring everything to a gentle simmer and let it cook for 20 minutes. If you're planning to freeze the soup, now's the time to cool it down and freeze it for up to three months.
If you're serving it right away, stir in half of the grated Parmesan and add the small pasta shapes. Cook for an additional 6-8 minutes, or until the pasta is tender.
To serve, sprinkle the soup with the shredded basil and the rest of the Parmesan cheese.
To serve, sprinkle the soup with the shredded basil and the rest of the Parmesan cheese. Enjoy!