Hello HeritagePantry. It is wonderful that you are revisiting such a timeless culinary foundation. Sofrito is truly one of the most rewarding techniques in home cooking, because it takes humble, affordable produce and transforms it into rich flavor.
To understand the ideal balance, it helps to know that sofrito has two main regional styles, depending on what kind of cuisine you wish to cook. In the Spanish tradition, sofrito is gently cooked down in olive oil until it forms a jam-like paste. In Caribbean traditions, such as Puerto Rican recaito or sofrito, the vegetables and herbs are often finely minced or pureed raw first, then cooked as needed.
For a classic Spanish cooked sofrito, a reliable balance by weight or volume is approximately two parts finely diced yellow onion to one part bell pepper (red or green), along with three to four cloves of minced garlic and two parts fresh grated or crushed tomatoes. The traditional method requires patience: heat a generous amount of good olive oil over low heat, add the onions first with a pinch of salt, and let them sweat slowly for 15 to 20 minutes until translucent and sweet. Add the peppers and cook for another 10 minutes, followed by the minced garlic. Finally, add the tomatoes and let everything simmer gently on low heat for 30 to 45 minutes until the moisture evaporates and the mixture turns deep red and fragrant.
For a Caribbean-style aromatic base, blend together roughly two medium onions, one green bell pepper, one red bell pepper, several sweet peppers if available, a whole head of garlic, a bunch of fresh cilantro, and a bunch of culantro or parsley. This produces a vibrant, raw aromatic puree that you can spoon directly into hot oil when starting a stew, soup, or rice dish.
When preparing large batches for everyday family meals, preservation is very straightforward. The easiest method is to ladle your prepared sofrito into silicone ice cube trays and freeze them solid. Once frozen, pop the cubes out into a sealed freezer bag. Each cube is roughly equivalent to two tablespoons, allowing you to toss one or two directly into hot oil, soups, or braises without thawing. Cooked sofrito will keep in the freezer for up to six months, or in a clean glass jar in the refrigerator covered with a thin layer of olive oil for about one week.
I hope this guide gives you the foundation you need to make comforting, flavorful meals for your family throughout the week.