Combine the dried spices then rub on all sides of the pork. Set aside.
3 pounds bone-in pork shoulder roast, ½ Tablespoon each: ground cumin, ground coriander, dried oregano, kosher salt, and black pepper
Toast ancho chile in a large skillet over medium heat until fragrant. About 3 minutes. Transfer to the slow cooker along with the chipotle peppers, onions, garlic and cola.
3 large dried guajillo peppers (or 6 small ones), 2 large chipotle chiles from a can, 1 large onion, 4 large garlic cloves, 12 oz can coca cola
On the same skillet, heat the oil over medium-high heat swirling to coat the bottom of skillet. Once hot, place the roast in skillet and cook for 3-4 minutes on each side to sear it.
1 Tablespoon avocado or vegetable oil
Transfer to slow cooker and cover with lid. Cook pork until meat is falling off the bone on high setting for about 6 hours or less.
Remove the meat to a large platter, rimmed sheet pan, or cutting board. Use two forks to shred the meat.
Skim and discard fat from surface of braising liquid, then puree liquid and solids with handheld blender. Stir in lime juice and brown sugar then the shredded pork. Mix everything together and taste. Add more salt if needed.
1 Tablespoon fresh lime juice, ½ Tablespoon brown sugar
Serve carnitas in warm tortillas with pickled onions, salsa, cotija and lime a squeeze of lime juice.