Directions

1. Whisk together beer, orange juice, lime juice, 2 tablespoons oil, garlic, 1 tablespoon salt, vinegar, Worcestershire sauce, black pepper, oregano, paprika, cumin, and cloves in a small bowl until spices are evenly incorporated.
   
2. Trim 2 green, and cut in half lengthwise. Using the palm of your hand against a flat work surface, lightly smash onions until a little moisture is released. Combine smashed onions, flap steak, white onion, chiles, cilantro, and beer mixture in a large bowl. Gently massage marinade into steak. Chill at least 2 hours or up to 12 hours.
   
3. Let stand at room temperature for 30 minutes. Remove steak from marinade and discard marinade. Preheat grill to very high. Place steak on lightly oiled grates. Grill, uncovered, until lightly charred in spots for medium-rare, 3 to 5 minutes per side. Transfer steak to a cutting board, and let rest 5 minutes.
   
4. Meanwhile, trim remaining 3 green onions; toss with remaining 1/2 tablespoon oil and dash of salt in a medium bowl until well coated. Place green onions on oiled grates, and grill, uncovered, turning occasionally, until softened and lightly charred, 2 to 4 minutes.
   
5. Cut onions into 2 inch pieces. Slice steak against the grain; serve with grilled green onions, warm tortillas, and salsa.