In a bowl, mix ground beef with sofrito, sazón, adobo, garlic powder, salt, and pepper. Form into 4 patties.
Cook patties on a flat griddle or skillet over medium-high heat for 4-5 minutes per side until cooked through.
Make the pink sauce by mixing equal parts ketchup and mayonnaise.
Butter the cut sides of the buns and toast face-down on the griddle until golden.
Assemble: bottom bun, pink sauce, patty, shredded cabbage, tomato slice, onion rings, more pink sauce, top bun.
Serve immediately while the bun is still warm and the patty is juicy.