In the best of all possible worlds, I would stroll/waltz/sashay out to my garden, pluck a dozen luscious, slightly over-ripe plum tomatoes from my thriving vines (growing in certified organic compost, etc.), throw them together with twelve other home grown/locally sourced, heirloom herbs and vegetables to make zuppa.
Though I occasionally entertain the possibility, I don’t live in best of all possible worlds, and canned tomatoes are a workhorse in my kitchen. This recipe is quite simple, easily a basis for any number of great soups.
Finely dice a small white onion; you want about a cup of root. Put a scant tablespoon or so of oil—olive oil is fine, of course, but that puts a stamp on your variants—in a 2-quart pan, add the onion, and cook on a low heat until the onions are soft and translucent.
This, children, is called “sweating,” and you do not want the vegetable to brown much, if at all. To this, add two cups of good, flavorful chicken broth, and a good Italian herb blend. Increase heat and let simmer for about fifteen minutes or so. Add 6 ounces of tomato paste and a 14-ounce can of diced/chopped tomatoes. Stew 30 minutes or so before serving.