In a small bowl, stir together miso paste, soy sauce, brown sugar, and chili crisp until well combined into a smooth paste.

Pat black cod fillets very well with paper towels to remove excess moisture. Cut each fillet in half, ideally along the line where pin bones run.

Coat fish pieces evenly with the miso paste mixture. Cover and refrigerate for at least 20 minutes and up to overnight (about 20 hours) for best flavor. Cook's Note: I've tested this air fryer black cod recipe with marination times of 20 minutes, 2 hours, 6 hours, and overnight. While overnight marination delivers the most developed flavor, even a quick 20-minute marinade produces delicious results you'll be proud to serve.

Remove fillets from refrigerator and let sit at room temperature for 20 minutes before cooking.

Preheat your air fryer to 375°F.

Use a pastry brush to ensure a relatively even coating of miso glaze on the fish.

If your air fryer basket is prone to sticking, cut heat-safe parchment to fit under the fillets to prevent sticking. Place the black cod fillets in the basket.

Cook at 375°F for 7-10 minutes, checking at 5 minutes to see if the fillets need to be rotated for even browning. The fish is done when it reaches an internal temperature of 135°F.

After cooking, you'll notice pin bones protruding along one edge. Gently remove them with your fingers, tweezers or kitchen shears before serving.

Serve garnished with sesame seeds, scallions, and a lime wedge.