Place pork chops in large resealable plastic bag. Combine ¼ cup cilantro, 2 tablespoons olive oil, 1 teaspoon lime zest, 2 tablespoons lime juice, 1 teaspoon garlic, and ¼ teaspoon crushed red pepper in small bowl. Add mixture to pork chops in bag; seal bag. Gently massage mixture on pork chops to evenly coat. Refrigerate 30 minutes or up to 2 hours.

Combine butter; remaining ¼ cup cilantro, 1 teaspoon lime zest, 2 tablespoons lime juice, 1 teaspoon garlic, and ¼ teaspoon crushed red pepper; salt and black pepper. Set butter mixture aside.

Preheat a charcoal or gas grill with greased grill rack for direct cooking over high heat (400°). Place a 12-inch cast iron skillet on grill rack; preheat 10 minutes.

Remove pork chops from marinade; discard marinade. Add pork chops to skillet. Cook 4 minutes, turning halfway through. Add half of butter mixture. Continue cooking pork chops 6 to 9 minutes or until pork chops reach 145°, basting frequently with butter mixture. Remove skillet from grill. Loosely cover skillet with foil and let chops rest 3 minutes.

To serve, top chops with remaining butter mixture. Garnish with lime wedges and additional cilantro, if desired.