- Rinse the fish fillets under cool water and dry them with paper towels.
- Whisk the oil, salt, garlic powder, onion powder, sugar, lime juice, and rosemary in a bowl. Transfer to a resealable bag with the halibut fillets.
- Seal the bag, move the bag’s contents around to coat the fish with marinade, and refrigerate for 1 hour.
- Preheat your Z Grills (preferably with branded apple, cherry, or hickory pellets) or other wood pellet grill to 250 degrees Fahrenheit.
- Remove the fish from the refrigerator and take it out of the marinade.
- Pat the fish dry with paper towels. If using butterflied fillets, tie the tapered ends together with butcher’s twine.
- Place the grill mat on the grates and transfer the fish to the grill mat. A grill mat is suggested since halibut tends to fall apart.
- Close the lid and smoke for 45-60 minutes or until the internal temperature reaches 145 degrees Fahrenheit.
- Remove the fish from the grill, plate, and serve with lime wedges.