In a mixing bowl, combine the liquid beef blood with 1/4 cup of vinegar. Stir well to prevent coagulation and set aside.
Heat cooking oil in a large pot over medium heat. Sauté the minced ginger, garlic, and onions until the onions are soft and translucent.
Add the beef chuck cubes. Cook until the meat is browned on all sides.
Pour in the fish sauce (patis) and cook for another 2 minutes to let the flavor absorb.
Add the beef broth (or water), dried bay leaves, and black pepper. Bring to a boil.
Lower the heat, cover the pot, and simmer for 60 to 90 minutes, or until the beef is fork-tender. Add more water if the liquid dries up.
Add the cubed beef liver and cook for 5 minutes.
Pour the remaining 3/4 cup vinegar into the pot. Bring to a boil and let it uncover without stirring for 3 minutes to cook off the strong acid taste.
Gently pour in the blood and vinegar mixture while stirring the stew continuously. This is critical to prevent the blood from curdling and to achieve a smooth gravy.
Simmer for 10 to 15 minutes on medium-low heat, stirring occasionally until the sauce thickens.
Add the brown sugar and siling haba (green chilies). Simmer for an additional 2 minutes.
Taste and adjust salt or pepper if needed. Serve hot with puto or steamed rice.