1) Pre-heat oil in a pan. Sauté garlic and onion until soft and translucent. Add ginger and continue sautéing until the aroma of ginger comes out. Add beef tail and continue sautéing until the juice of beef tail comes out.
2) Transfer the sautéd beef tail in a pan and add water until the beef is fully submerged in water. Simmer for 1 hour if using a pressure cooker or 1 1/2 hours if using ordinary pan or until the meat is tender. Add more water if needed.
3) Once the meat is tender, add sinigang mix and season with salt and pepper adjust according to your taste. Lastly, add the bell pepper and continue to simmer till the bell pepper is cooked. Remove from the heat and ready to serve. Enjoy!