The key to this adobo is truly burning the chiles and spices. Try this at home; just open the windows and turn on the fan first.
- 8 dried cascabel or 2 pasilla chiles, seeds removed
- 3 ancho chiles, seeds removed
- 3 dried guajillo chiles, seeds removed
- 3 pasilla chiles, seeds removed
- 6 red jalapeños or Fresno chiles, halved, seeds removed
- 4 corn tortillas, plus more, warmed, for serving
- 1 teaspoon Mexican or Italian oregano
- 1 teaspoon allspice berries
- 2 cups fresh orange juice
- 2 pork tenderloins (about 2 pounds total), trimmed, silver skin removed
- Guacamole, Grilled Salsa Roja and Avocado-Tomatillo Salsa Verde, and lime wedges (for serving)
Preheat oven to 500°. Roast cascabel, ancho, guajillo, and pasilla chiles on a rimmed baking sheet until completely blackened, about 5 minutes. Transfer to a large bowl and pour in cold water to cover; let sit 30 minutes to soften. Drain.
Meanwhile, roast jalapeños, garlic, and 4 tortillas on a clean rimmed baking sheet until blackened and charred, 12–15 minutes.
Heat a dry small skillet over medium-high and toast oregano and cumin seeds, tossing often, until beginning to burn, about 1 minute. Transfer oregano and cumin to a small bowl. Char cloves and allspice, tossing often, until black and ashy, about 4 minutes.
Purée softened chiles, tortillas, jalapeños, garlic, oregano, cumin seeds, cloves, allspice, orange juice, and salt in a blender until smooth. Place pork in a large bowl and pour adobo over (meat should be submerged). Cover and chill at least 6 hours and up to 12 hours.
Remove pork from adobo, leaving as much paste on meat as possible, and let sit at room temperature 1 hour.
Prepare a grill for medium-low heat. Grill pork, turning once after first 20 minutes, until an instant-read thermometer inserted into the thickest part registers 145°, 35–45 minutes. Transfer to a cutting board and let rest 15 minutes before thinly slicing.
Serve pork with tortillas, guacamole, Grilled Salsa Roja, Avocado-Tomatillo Salsa Verde, and lime wedges.