Gather peppers, onions, garlic, vinegar, oil, salt, and water
Wash and chop the peppers
Peel and chop the onions and garlic
Heat oil in a pan
Sauté the onions and garlic until soft
Add the chopped peppers and cook briefly
Add vinegar, salt, and a little water
Simmer until the mixture softens
Blend or mash the mixture until smooth
Return to the pan and cook until the sauce thickens
Taste and adjust salt or vinegar if needed
Let cool before serving or storing