In a large glass or ceramic bowl, combine the orange juice, lemon juice, and lime juice.

Stir in cilantro, soy sauce, garlic, chili powder, cumin, paprika, black pepper, chipotle pepper, and oregano until well blended.

Place your flank or skirt steak in a resealable bag or shallow dish and pour the marinade over the meat. Seal or cover and refrigerate for at least 4 hours, ideally 24 hours.

Preheat grill to medium-high heat (about 400°F). Clean and oil the grates.

Remove steak from the marinade, let excess drip off, and grill 6–8 minutes per side for medium-rare.

Transfer steak to a cutting board, cover loosely with foil, rest for 5 minutes, then slice against the grain.