Preheat the air fryer: Set it to 400°F (200°C) for 5 minutes so the basket is hot when the fish goes in.
Prep the fish: Pat the basa fillets dry with paper towels. Dry fish equals a crisper crust. If the fillets are very thin, you can stack two for a thicker portion.
Set up your dredging station: On one plate, mix the flour with a pinch of salt and pepper.
In a shallow bowl, whisk the egg with the Dijon. On another plate, combine panko, fine breadcrumbs, Parmesan, garlic powder, onion powder, smoked paprika, remaining salt, and pepper.
Coat the fillets: Lightly dust each fillet in the flour, shaking off excess. Dip into the egg mixture, then press into the breadcrumb mix. Pat gently so the crumbs adhere, especially on the sides.
Oil the surface: Spray both sides of the coated fish with cooking spray.
This encourages even browning in the air fryer.
Air fry in batches: Place fillets in a single layer in the preheated basket. Don’t crowd them. Cook at 400°F (200°C) for 8–10 minutes, flipping halfway.
Thinner fillets cook faster; thicker ones may need a minute or two more.
Check doneness: The crust should be golden and crisp, and the fish should flake easily with a fork. An instant-read thermometer should read 145°F (63°C) at the thickest point.
Serve: Squeeze fresh lemon over the top, sprinkle with herbs, and plate with your favorite sides—think simple salad, steamed green beans, or crispy potatoes.