The problem with simply heating up the sealed jars is that during normal processing, the goal is to drive all air out of the headspace (the space between the food and the lid). That’s why you only put the lids on finger tight instead of cranking them on as tight as you can. While boiling, the air is forced out, and then the vacuum formed by lack of air sucks down the lid, making a tight seal. No air trapped in the top of the jar = no opportunity for microorganisms that need air to grow to spoil your salsa. If the pH is low enough, botulism (which releases spores in an anaerobic (no oxygen) environment) will also be out of commission. (For more on botulism in canning, read here – https://commonsensehome.com/botulism/.)
It needs to be cooked ahead of time so that the flavors are blended and you can taste it and make sure it’s how you want before canning. With the big pot for canning, I have a quilted hot pad under them instead of a rack. I never bought a rack because the hot pads work just fine. You need something under the jars but it can be as simple as a kitchen towel (I have not broken a jar in 3 years! So it must be okay, lol). I have some posts on the water bath method that explain my equipment in more detail.
Chris Munn, it's so nice to meet someone with Peruvian connections! What a treat that your wife has introduced you to so many Peruvian favorites. I've found that Peruvians are very proud of their cuisine and every region has their own specialties. I'm glad you found this salsa recipe. It's simple to prepare and my favorite salsa. Thanks for coming by and leaving a meaningful comment.
Absolutely love this. You were right. Getting as much water out is so really important step. I drained as best I could with colanders then put in glass bowl. More liquid settled so I used a turkey baster to remove more liquid. Won’t ever make it another way. I have been looking for a salsa that has body and flavor and this is outstanding. I made my own tomato sauce as the tomatoes I got from local farmer were meaty and very flavorful. Thank you for posting this outstanding salsa recipe.