Prepare the chiles by removing the stems and seeds. Roast the chiles in a dry, heavy-bottomed pan, like an iron skillet, over medium-high heat.
Once the chiles are roasted and cooled, briefly cut or tear them into smaller pieces and process them in a spice grinder. Working in batches, sieve the chiles through a fine-mesh strainer to remove any pieces that weren't completely ground.
Roast and grind the cumin seeds. This will extract the full flavor from the cumin. Sieve the cumin seeds as you did the chiles, and discard anything that didn't get ground. (Alternatively, use pre-ground cumin to save time.)
Once all of the chiles/cumin have been ground, add the dry spices (ancho, morita, oregano, cocoa powder, cumin, espresso powder [optional], cinnamon, sea salt, and coarse black pepper) to a bowl and mix thoroughly to combine.