Step 1

Bring 4 cups water to a boil, then remove from heat.

Step 2

Remove the stems and seeds from the dried chile de arbol peppers. Removing the seeds is optional for a smoother, less seedy salsa.

Step 3

Dry toast the chile de arbol peppers in a dry pan, about a minute per side. This will help loosen them and release their natural oils.

Step 4

Add the toasted peppers to a bowl and cover with the very hot water. Soak them for 15 minutes, or until the peppers are softened. You may need to stir a bit to make sure all of the peppers are submerged.

Step 5

Heat the olive oil in a large pan. Add the onion and cook for 4-5 minutes to soften. Add the garlic and cook another minute, until you can smell the garlic. Add it to a food processor or blender.

Step 6

Add the rehydrated peppers to the food processor or blender along with the onion, garlic, cilantro (if using), lime juice and salt.

Step 7

Process until smooth.

Step 8

Taste and adjust with salt and a few splashes of water for a thinner salsa.

Step 9

Add all of the ingredients to a food processor. Process until smooth.

Step 10

Pour the mixture into a small pot and bring to a boil. Reduce heat and simmer for 10 minutes.

Step 11

Cool and serve.