
Remove the top of the chiles and shake out most of the seeds.
In a large pot, add the chiles salt, pepper and oregano.
Add enough water to cover all of the chiles.
Cover and cook on medium heat for about 20 minutes or until they're very soft and pliable. Rest chiles in the water for another 10 to 15 minutes to cool off.
Transfer chiles to a blender or food processor and add 1 cup broth (do not add the cooked water). Puree for about 1 minute.
Place a fine mesh strainer over a large bowl and pass the pureed chiles to remove the remaining seeds and skins (tip: push the chile mix with a spoon to get the most out of them).
Repeat the process until all of the chiles are blended and strained. Taste for salt and pepper and add more according to taste if necessary.
Discard the seeds and skins left in the mesh strainer.
Note: The flavor may be strong at this stage but it changes for the better once it's mixed into your recipe for tamales or pozole.
Store in jars in refrigerator for up to 2 weeks or freeze until ready to use.