Add the beef stock, lime juice, onion, chipotle peppers, garlic, oregano, cumin, bay leaves, salt, and pepper to the Dutch oven.
Mix well.
Cover with a lid and place in the oven. Cook for 3 hours, turning the meat once halfway through the cooking time.
While the barbacoa is cooking, prepare the lime crema by adding the sour cream, lime juice, and lime zest to a small bowl.
Mix well, cover, and refrigerate until ready to use.
Remove the barbacoa from the oven. Using two forks, shred the meat. Keep warm.
Make the bowls: Add the olive oil to a saute pan over medium heat.
Add the corn, beans, cumin, salt, and pepper.
Stir and cook until heated through, approximately 2 minutes.
Assemble the barbacoa bowls by dividing the rice between 4 bowls and adding the bean and corn mixture, avocado slices, and barbacoa to each bowl. Garnish each bowl with lime crema, cilantro, and lime wedges to serve.