Try adding half a tomato for starters, then add more to taste. Keep a glass of milk handy to cool off after your taste tests!   

Remember you can always add more, so mix in additional flavors little by little and taste as you go.

Add a teaspoon at a time until you’ve gotten your salsa under control. If you have any leftover, it’ll make a great condiment for tacos, sandwiches, eggs, and stir fries.

If you’re serving salsa at a party, it might be best to stick to a recipe you know. Tweaking your salsa by adding new ingredients is like an experiment, and you might not want to use your guests as guinea pigs.

Acid in the salsa helps prevent bacterial growth, but it still shouldn’t be left out for more than a couple hours. [6] X Trustworthy Source US Food and Drug Administration U. S. government agency responsible for promoting public health Go to source

If you have a large stainless steel roasting pan or saucepan, try pouring half of each batch into it. You should then have enough room in your mixing bowl to add the rest of the second batch. Avoid aluminum products, which will react with the acid in the salsa and leave your dish with an unpleasant metallic taste. [7] X Research source You could also use the largest freezer bags you have to mix your batches.  

Simmer your salsa uncovered in deep saucepan over low heat, and stir frequently. Depending on your salsa’s water content, simmer it for up to 60 minutes, or until you’ve achieved a thick consistency.

If you accurately doubled the ingredients other than peppers in a suitable salsa recipe, your double batch should still be acidic enough for canning. It’s vital to accurately double the acidic ingredients without overdoing the non-acidic ingredients. If you’re not sure about your accuracy, just freeze the leftovers.