Finely chop, dice or use your food processor on the onions, celery, basil and ... a few hours to reduce it to the thickness you prefer! Fill jars with hot tomato soup, leaving 1/2-inch headspace.

but basil would work just as well. Broth: I usually have chicken broth on hand, but you can substitute it for vegetable broth. Some tomato soup recipes call for cream or milk, which you can add ...