Quarter 1 onion and put in a pot with the beef. Add water until beef is covered.

Bring water to a boil and boil until beef is soft enough to shred (~1.5-2 hr). Skim foam off water if it appears. Fill with water as needed to maintain water level.

While that is happening, dice the other onion, the pepper(s), and tomato (if not using canned tomatoes). Chop garlic into small pieces as well.

When beef is ready, shred it apart. Save the water that was used.

Add oil to a large pan and sautee the diced onion, pepper and garlic until onion is soft and translucent.

Add the diced tomato (or can of tomatoes) and shredded beef to the pan. Mix everything together.

Add the saved water used to boil the beef to the pan until everything is covered. Add salt, pepper, cayenne pepper, paprika, beef stock cube, and a few dashes of Worcestershire sauce. Add tomato paste if wanted. Mix well.

Bring to a boil, then reduce heat and simmer (medium-high heat) for 20-30 min until desired amount of liquid is left.

Season as needed to your tastes.

Serve by itself, in an empanada, or inside an arepa.