Halve and seed the jalapenos.

Chop the large onion.

Mince the garlic cloves.

Combine the halved jalapenos, chopped onion, and minced garlic in a pot.

Add just enough water to the pot to steam the vegetables without fully covering them.

Simmer the vegetables until they are tender.

Remove the pot from the heat once the vegetables are tender.

Add salt, vinegar, and oil to the pot.

Puree the mixture in a food processor until smooth.

Optional: Blend in sour cream to tame the heat, if desired.

Adjust vinegar to taste, adding a little more to tame the heat.

Store the salsa in the refrigerator, but note it doesn't can well.