The key to the authentic flavor is Sazón (a traditional blend of spices and herbs, often with added vinegar/lime) and the technique of caramelizing sugar at the beginning of cooking the meat, which gives the Carne Guisada a rich, dark color.
Habichuelas Guisadas (stewed beans) must be thick and creamy. Typically, part of the beans are mashed or blended to achieve the correct sauce consistency.
Wash, pat dry, and marinate the beef in a mixture of Sazón, minced garlic, oregano, and lime juice. Marinate for at least 30 minutes, ideally 2 hours in the refrigerator.
In a large pot or caldero, heat the oil and add the brown sugar. Let it caramelize until dark brown (but not burnt).
Add the marinated meat to the pot. Sear on all sides until it achieves a rich, dark color from the caramel.
Add the tomato paste and mix with the meat. Add water/broth so the meat is largely submerged.
Bring to a boil, reduce the heat, and simmer covered until the meat is tender (approximately 1-1.5 hours). The meat should be tender enough to shred with a fork. If the gravy is too thin, cook the last 15 minutes uncovered until it thickens.
In a second pot, heat the oil and sauté the diced onion, celery, bell pepper, and garlic (the soffrito). Sauté until the vegetables soften.
Add the tomato paste, oregano, and cilantro. Heat briefly.
Add the beans along with their liquid (from the can or cooked dry beans with water). Bring to a boil and simmer for 15-20 minutes over low heat.
For a creamier consistency, take about 1/3 of the beans, mash them with a fork (or blend), and return them to the pot. Season with salt and pepper.
Prepare the Arroz Blanco (white rice) and Tostones (if using).
On a plate, serve a mound of white rice, a portion of stewed beans next to it, and the braised meat with gravy on the third side. Add a green salad and avocado slices.
Serve immediately hot.