Preheat the oven to 325 degrees F.
Mix the oregano, chipotle powder, cumin, salt and pepper together in a small bowl.
Season the cubed pork chunks with the spice mixture and put into a large Dutch oven. Add the onion, garlic, chicken stock, the tomato puree, honey, orange and lime juice, and the juiced orange and lime halves. Stir together with a wooden spoon. Put the pot on medium heat and bring the mixture to a simmer. Transfer to the oven and cook, covered, until the pork is tender and easily shreds, about 1 hour and 45 minutes.
Remove the meat from the Dutch oven to a cutting board. Set the Dutch oven over medium heat and reduce the liquid until it becomes slightly syrupy, about 10 minutes. Meanwhile, shred the meat and add to a bowl. Drizzle the reduced cooking liquid into the pork and toss. Serve with tortillas, cilantro, sour cream and Zesty Slaw.
Whisk the rice wine vinegar, lime juice, canola oil, and sugar together in a small bowl.
Add the cabbage, cilantro, green onions, and carrot to a large serving bowl and combine. Drizzle with the dressing and toss to coat. Season with salt and pepper, to taste, and serve.