Add the flank steak, beef broth, and bay leaf to a Dutch oven or large pot. Bring to a boil, and then reduce the heat to a low simmer. Simmer for 45 minutes, or until fork-tender. Flip the beef over halfway through the cooking time.

Remove the steak from the broth, and place on a cutting board. With a fork, lightly shred the meat until you have a thin, shredded texture. Reserve the broth.

In a large bowl, combine the shredded beef, garlic, salt, pepper, lime juice, and reserved broth. Marinate the meat in this mixture for at least 20 minutes.

Once the meat is done marinating, heat 2 tablespoons of oil in a large frying pan. Using a pair of tongs, pick up the shredded beef out of the marinade, and place in an even layer in the hot skillet. Fry without stirring for 4 - 5 minutes, or until crispy.

Carefully turn the meat over, and fry on the other side for an additional 4 minutes. The meat should be nice and crispy. Remove from the frying pan, and place on a serving platter.

In the same frying pan, heat the remaining tablespoon of olive oil over medium heat. Add the sliced onion, and saute for 4 minutes or until the onions are tender. Arrange the cooked onions on a platter with the meat. Serve with fresh lime wedges.