First, prepare the peppers for the adobo sauce: In a pot, boil 12 guajillo peppers, 2 ancho peppers, half a white onion, and 3 bay leaves for 10 minutes. While the peppers are boiling, you can optionally toast 1 teaspoon cloves, 1 teaspoon cumin, 2 cinnamon sticks, 2 teaspoons Mexican oregano, and 1 tablespoon peppercorn.
Once the boiled ingredients are ready, combine them in a blender (or food processor) with the toasted spices (if used), 5 cloves garlic, 4 chipotle peppers, 2 teaspoons salt, 4 tablespoons achiote paste, 1 tablespoon onion powder, 1 tablespoon garlic powder, 1 cup pineapple juice, 1 1/2 cups pepper water, 1/4 cup orange juice, and 1/4 cup apple cider vinegar. Blend until smooth to create the adobo sauce.
Marinate the 7 lb pork shoulder in this adobo sauce for 5 hours.
Preheat your grill to 350 F - 400 F. Grill the marinated pork shoulder for 1 hour 30 minutes, or longer if needed, until cooked through and tender.
While the pork is grilling, prepare the tomatillo salsa: In a blender, combine 3 toasted tomatillos, 4 cloves garlic, 1/2 cup cilantro, 1 jalapeño, 1/2 teaspoon onion powder, and 1/2 teaspoon garlic powder. Blend until smooth.
Once the pork is done, slice it thinly and serve in tacos with the tomatillo salsa.
