This paste serves as a base for many recipes.
Remove tops and seeds from chilies. Rinse. If your sensitive to heat, wear gloves while performing this task.
Soak cleaned chilies in boiling water to cover for 30-60 minutes. Check after 30 minutes to see if they are soft. If they are starting to fall apart, they are ready. If not, let soak a little longer. You may need to weigh down chilies in boiling water with a plate or bowl so they stay submerged.
Drain soaked chilies, saving 1/4 cup water. Place in high-powered blender or food processor with olive oil and salt. Process until completely smooth, about 5 minutes. If the mixture is too thick for the machine to process, add just enough water.
Store in a closed container in the refrigerator, covered with a thin layer of oil.