To prepare meatballs, add beef and all the other ingredients in a bowl and mix together until well combined.
Shape beef mixture into meatballs, about 15 medium or 8-10 large.
Heat olive oil in a large skillet over medium heat.
Add meatballs to skillet and cook for a few minutes until brown on all sides. Remove from heat. Please note, the meatballs won't be fully cooked yet.
Heat a saucepan over medium heat. Add sofrito, tomato paste, chicken bouillon, onion and peppers. Cook for 2-3 minutes until fragrant. Add water, vinegar, oregano, sazón, olives and cilantro (if using).
Add the meatballs and roll them in the sauce to make sure they are evenly coated.
Cover, reduce heat and simmer for 15-20 minutes or until sauce thickens. Remove the cilantro sprigs.
Serve over rice or with your side dishes of choice. Enjoy!