Preheat the air fryer to 390°F (200°C). Give it 3–5 minutes so the basket is hot. A heated basket helps the fish cook evenly and brown a bit on the edges.

Pat off any surface frost. If the fillets have ice crystals, run them under cool water for a few seconds, then pat dry. This keeps seasoning from sliding off and prevents steaming.

Brush with oil. Lightly coat both sides of the frozen fillets with olive oil or melted butter. This helps the spices stick and improves texture.

Season generously. Mix salt, pepper, garlic powder, paprika, and onion powder. Sprinkle on both sides. Add lemon zest for a pop of freshness.

Arrange in the basket. Place fillets in a single layer, not touching. If your air fryer is small, cook in batches so air can circulate.

Air fry for 6 minutes. This jump-starts cooking and releases extra moisture from the surface.

Flip and continue 5–7 minutes. Cook until the fish flakes easily with a fork and is opaque all the way through. Target internal temperature: 145°F (63°C).

Finish with lemon and herbs. Squeeze fresh lemon over the fillets. Add chopped parsley or dill for color and freshness. If you like, spoon on the simple lemon butter sauce.

Serve right away. Pair with rice, quinoa, roasted veggies, or a crisp salad.