In a large bowl, whisk together orange juice (¾ cups), lime juice (½ cups), garlic (6 cloves), cilantro (½ cups), jalapeño (1 whole), olive oil (¼ cups), salt (1 tsp), and pepper.

Add flank steak (1000 g) to the marinade, ensuring it's fully submerged. Cover and refrigerate for at least 4 hours, or preferably overnight.

Preheat grill to medium-high heat.

Remove steak from marinade and discard marinade.

Grill steak for 5-7 minutes per side for medium-rare, or until desired doneness is reached.

Internal temperature of 130-135°F for medium-rare • Smoky aroma and slight charring on the surface

Let the steak rest for 10 minutes before slicing against the grain.

Slice the steak thinly against the grain and serve immediately.

Thin, even slices