In a large dutch oven, heat the olive oil over medium high heat. Add the pork and cook until browned. Add the garlic and onions, stir into the pork, cover and simmer for 3-4 minutes until tender. Add the cumin, oregano, chili powder, salt, pepper, chicken broth, black beans and chilies. Stir to combine, cover tightly with lid and place in the oven.
Cook for 2 1/2-3 hours until pork is tender. Stir in the corn and serve in bowls with tomatoes, avocado and cilantro to garnish.