In a blender, combine olive oil, garlic, jalapeño, cilantro, 1 teaspoon of kosher salt and several turns of freshly ground pepper, lime juice, orange juice and white vinegar.

Blend until well combined.

Place flank steak in a shallow dish and pour marinade over, turning to coat.

Cover and let marinate in refrigerator for at least 1 hour but no longer than 8 hours.

Before grilling, let flank steak come to room temperature.

Remove from marinade and shake to remove excess.

Gently pat steak dry and season with additional salt, pepper and 1/2 teaspoon of garlic powder.

Heat grill to high and cook steak 5-7 minutes per side depending on thickness until medium rare.

Let steak rest 10 minutes, then slice against the grain.