In a large pot, add beef broth and the steak, bring to a boil. Turn the heat to medium and cook for 45 minutes. Remove the meat and shred once cooled. Place the meat back into the broth and add salt, garlic powder, black pepper, and lime juice.
Heat the oil in a large skillet over medium-high heat. When the oil is hot, add the shredded beef. Cook the beef until the bottom is crispy, then flip to cook the other side. Remove the beef from the skillet once crispy, then cook the onions for a few minutes. Combine the beef and onions, and serve with white rice, plantains, and limes!