In a large pot, combine the cubed pork shoulder, onions, avocado leaves, black pepper, salt, garlic, and bay leaves. Add enough cold water to cover the meat. Bring to a boil over high heat, then continue to boil for 20 minutes.
2. Step
Add the orange juice, milk, and cola, return to a boil, and simmer until the liquid has reduced by half, about 1 hour.
3. Step
Add the lard, let it melt, then boil off the rest of the liquid until the meat begins to fry, 1 hour more.
4. Step
Once the meat turns dark golden brown and crispy, scoop it out of the pot and onto a paper bag or paper towel-lined baking sheet to drain.
5. Step
Serve with corn tortillas, guacamole, pickled vegetables, cilantro, lime wedges, cilantro rice, and pinto beans.