Toasting the dried chiles before boiling them revives their flavor and helps extract even more of it into the final adobo. When boiling the chiles, pile the onion pieces on top to keep the chiles submerged. This adobo is also part of Claudette Zepeda's Birria Tacos recipe.
How to Make It
Heat a large cast-iron skillet over medium. Add chiles to skillet; cook, stirring occasionally, until fragrant, 4 to 5 minutes. Transfer chiles to a large saucepan; add onion, garlic, ginger, and 6 cups water. Bring to a boil over medium-high. Cook, uncovered, stirring occasionally, until chiles are softened, about 8 minutes. Drain chile mixture; discard cooking liquid.
Combine chile mixture, vinegar, salt, black pepper, oregano, cumin, cinnamon, cloves, thyme, bay leaves, and remaining 2 cups water in a blender. Secure lid on blender, and remove center piece to allow steam to escape. Place a clean towel over opening. Process until smooth, about 45 seconds. Let cool to room temperature, about 1 hour. Cover and chill until ready to use.