Use kitchen shears or a cleaver to cut the rock lobster tails in half. Lightly char green onions alongside the tails on the grill. We like dousing the tails in Mexican hot sauce, such as Cholula, for authentic flavor. Serve with ice-cold Mexican beer.
1. Preheat grill.
2. To prepare lobster, cut each lobster tail in half lengthwise. Coat lobster tails and onions with cooking spray. Place lobster tails, cut sides down, on grill rack coated with cooking spray; grill 3 minutes. Turn lobster; grill 5 minutes. Place onions on grill rack; grill 3 minutes or until tender.
3. To prepare sauce, combine rind and next 7 ingredients (through garlic) in a medium bowl, stirring well with a whisk. Gradually add butter, stirring constantly with a whisk. Drizzle sauce over cut sides of lobster tails.
4. Warm tortillas according to package directions. Serve with lobster and lime wedges, if desired.