Clean, seed and devein chilies. Cover with water and bring to a boil in a large saucepan.
Turn off heat and place a heavy plate on top of the chilies to keep them submerged in the hot water. Let steam for at least 15 min until the chilies are very soft.
Remove chilies from water and place in a blender. Add garlic, onion, arbol chilies, chicken broth or water and spices. Blend on high for 5 min.
In saucepan, heat oil. Add in enchilada sauce and simmer for a few minutes to remove the bitterness of the chilies (sometimes I omit this step, also with good results).
Taste for salt and add more as necessary. Use the sauce right away or transfer to an airtight container and refrigerate for up to 7 days.