Prepare the beef: Trim excess fat, pat dry, and season with salt, pepper, and cumin.Sear the beef: Heat olive oil in a pot or Dutch oven, brown beef on all sides, then remove and set aside.Sauté vegetables: In the same pot, cook onions, red and green bell peppers, and garlic until soft and slightly caramelized.Build the sauce: Add tomato sauce, tomato paste, beef broth, white wine, oregano, bay leaf, salt, and pepper. Mix well.Slow-cook the beef: Return beef to the pot, reduce heat to low, cover, and simmer for 2–3 hours until tender. Slow cooker alternative: 6–8 hours on low.Shred the beef: Remove beef, let cool slightly, shred with two forks, and return to the pot with the sauce. Add olives and capers if using.Final touches: Simmer 10–15 more minutes, adjust seasoning, and garnish with fresh cilantro or parsley before serving.