Cut the pork shoulder into roughly baseball-sized chunks.
Separate and peel the cloves of garlic. Combine the garlic, cumin and salt in a food processor and process until a paste forms. Rub the paste over the pork chunks.
Place the pork chunks in a slow cooker with the coca-cola. Juice the oranges and add the juice and the peels into the slow cooker. Cover, and cook on low heat for 8-10 hours.
Heat the oil in a large skillet. Remove the chunks of meat from the crockpot, and fry them in the oil until a crust forms. Alternativey, break the meat into smaller chunks, spread it on a baking sheet, and broil for 5-10 minutes until crisp on top. Loosely shred the meat, and serve.
Notes
If you don't have a slow cooker, you can still make these carnitas! Bake them, covered, in a dutch oven with a lid - 45 minutes at 450 degrees, then 350 degrees for another 3 hours.
Recipe by The Domestic Front at http://www.thedomesticfront.com/crockpot-mexican-pork-carnitas/