Prep the air fryer: Preheat to 390°F (200°C) for 3–5 minutes. Lightly oil the basket or use a perforated parchment liner to prevent sticking.

Pat the cod dry: Use paper towels to remove as much moisture as possible. Dry fish browns better and won’t steam.

Season the fillets: Brush both sides with olive oil. Sprinkle with paprika, onion powder, 1/2 teaspoon salt, and black pepper. Zest half the lemon over the fillets for extra brightness.

Make the lemon butter: In a small bowl, combine melted butter, minced garlic, remaining lemon zest, and the juice of half the lemon. Whisk until smooth.

Load the basket: Place the cod in a single layer with space between pieces. Spoon about half of the lemon butter over the tops.

Air fry: Cook for 8–10 minutes, depending on thickness. Thicker fillets may need up to 12 minutes. It’s done when the fish flakes easily and reaches 135–140°F (57–60°C) internally.

Finish: Spoon the remaining lemon butter over the hot fillets. Squeeze the rest of the lemon over the top if you like a brighter finish.

Garnish and serve: Sprinkle with chopped parsley. Add a small pat of butter on each fillet for extra gloss, and serve with lemon wedges.