Slice the beef into cubes and marinate in soy sauce, calamansi juice, garlic, and black pepper for 2–4 hours (or overnight for best flavor).
Heat oil in a pot over medium heat.
Sauté onions and garlic until fragrant.
Add the marinated beef (reserve the marinade) and brown on all sides.
Pour in beef broth and the reserved marinade.
Add banana ketchup, brown sugar, and annatto powder.
Optional: Add fish sauce, star anise, or coconut milk for extra depth.
Bring to a boil, then reduce heat to low.
Cover and simmer for 1.5 to 2 hours, stirring occasionally, until beef is tender.
If sauce thickens too much, add a bit of water or broth.
Taste and adjust seasoning as needed.
Optional: Stir in chili paste for a spicy version.
Serve hot over garlic rice or with steamed vegetables.
Garnish with fresh herbs, microgreens, or a squeeze of calamansi.