Made this yesterday and would make again!
In slow cooker, put one finely chopped onion , garlic and pepper. Add tin of tomatoes. mix up and add 1 teaspoon of molasses, salt and pepper, basil. Add about 500mls of stock with a good dollop of tomato puree.
Leave on high for 4 hour hours, turn down to low heat and add some spagetti bits, about 2 inch long pieces. That will then soak up the juices and be ready in about 45 mins :)