Directions

1. Place pork in a shallow baking dish and pour over vinegar; turn to coat. Let stand for 15 minutes and up to 2 hours.
2. Preheat oven to 350 degrees. Heat vegetable oil in a Dutch oven. Season pork with salt and pepper and, working in batches, add to Dutch oven. Cook until browned on all sides; transfer pork to a plate and set aside.
3. Add onion, garlic, cocoa powder, cumin, cinnamon, cardamom, and chipotle chiles to Dutch oven. Cook until onion is soft and spices are fragrant, adding a little water if mixture begins to stick to the bottom of the pot.
4. Return pork to Dutch oven; stir to combine. Add 1 cup water, sweet potatoes, and turnips; do not stir. Cover and transfer to oven. Cook until pork is tender and vegetables are soft, about 1 1/2 hours. Serve hot with rice, if desired, and garnished with tomato and cilantro.