Pat cod fillets dry with paper towels to remove excess moisture. Brush lightly with olive oil, then season with salt, pepper, and sprinkle garlic powder.

Mix together Parmesan cheese, panko bread crumbs, and lemon zest in a shallow dish.

Press the mixture onto both sides of the cod fillets, ensuring each piece is generously coated. Allow to rest for 2 minutes.

Preheat air fryer, then place fillets in a single layer in the basket. Air fry for about 15 minutes, or until golden brown and fish flakes easily.

Drizzle with homemade lemon-butter sauce and sprinkle with fresh parsley before serving.