Cut beef into 2x2 inch pieces. Season with salt, pepper, cumin and oregano. Place in a slow cooker.
Add lime juice, Bay leaves, chipotle chilis in adobo and broth. Add garlic and onion. Cook on high for 6-7 hours, until tender.
Remove meat and transfer to a cutting board. Shred with 2 forks.
Strain the cooking liquid and reserve all or some of it foe serving.
Return meat to the pot and keep it warm.
Optional: To crisp up the meat, before you serve it, you can heat 2 tbsp oil on a skillet and lightly brown it for 2 minutes per side, turning once).