Fry the onion and garlic with the butter in a large saucepan and fry for 5 minutes. Add potatoes and carrots, and cook for a further 5 minutes.
Add the tomatoes, stock, and herbs, simmer for 25 minutes or until all the vegetables are just tender.
Add the macaroni and cook for 20 minutes or untill softened. Now add the petit pois and cook for 10 minutes.
Finally add the baked beans (I suggested Heinz baked beans because it isn't too sweet, but any other not-too-sweet baked beans will do) and cook for 5 minutes and serve, topped with Parmesan (or Cheddar) and chopped parsley.