I recently tried some Heinz tomato soup. I used to adore this as a kid, but as an adult, meh. This is my recipe for real home-made tomato soup, made from real tomatoes, and it's real tasty. Also easy to make and cheap too.
Peel and chop the onion and gently sauté in the butter until softened but not browned. Wash the tomatoes and basil in cold water. Remove any stems from the tomatoes, and chop them into quarters. Roughly chop the basil (stalks an' all). Pour the stock into a large saucepan, add the tomatoes and basil, and the onions when they are softened. Bring to the boil, cover with a lid, and simmer for half an hour, stirring occasionally.
After half an hour, add the sugar and salt, and taste the tomato soup. Add more sugar or salt if required. Pour the whole lot into a blender (or do it in batches if it won't fit), and blend until smooth. Pass it through a fine sieve, pressing the pulp through with the back of a spoon. You may need to do this process a couple of times until you are left with a really smooth tomato soup.
When ready to eat, re-heat the soup and serve with croutons and a garnish of basil leaves.
Ground black pepper to taste. It's best to use overripe tomatoes for this - they might not look great, but they'll be full of flavour, and cheap too.