Whisk together the orange juice, lime juice, olive oil, minced garlic, cumin, chili powder, smoked paprika, cilantro, salt, and pepper in a bowl until combined.

Place the skirt steak in a zip-lock bag or shallow dish. Pour the marinade over the steak, press out the air, and seal. Refrigerate for at least 4 hours, or overnight (8–12 hours) for best results.

Remove the steak from the fridge 30 minutes before cooking to bring it to room temperature.

Heat a cast iron skillet or grill to screaming hot — high heat for 3–4 minutes until just beginning to smoke.

Remove the steak from the marinade and pat lightly with a paper towel. Place on the hot surface and cook undisturbed for 3–4 minutes. Flip once and cook another 3–4 minutes for medium (140–145°F internal temperature).

Transfer to a cutting board and rest for 5 minutes. Slice thinly against the grain and serve immediately.