In a small mixing bowl, mix the ketchup, mayonnaise, orange juice, and Worcestershire sauce. Set aside in the fridge.
Pulse onion, garlic, bell pepper, salt, pepper, and Worcestershire sauce in a food processor until you obtain a coarse paste.Mix the seasoning paste with the meat. Divide meat into 6 portions and form 6 patties (round for hamburger bread, oval-shaped for pan de agua).
Brush a stove-top grill, heavy skillet, or large griddle with some of the oil and heat over high heat. Grill the patties, rotating until they are cooked through. Set the cooked burgers aside.
Reapply some oil to the grill, lower the temperature to medium-high heat, and warm the bread.
Reapply oil to the grill, and sear onion and tomato slices. Mix the cabbage with half the sauce made in step 1. Turn down the heat to medium and briefly cook the cabbage. Heating the cabbage is an optional step.
Put meat, onions, tomatoes, and cabbage on the bottom half of the buns, and garnish with the remaining sauce. Top burgers with the other halves of the bread.You can briefly put them back on the grill and press lightly if you want.
Serve right away. Goes great with an ice-cold beer.
