Start by using fresh fish or frozen fish that has been completely thawed. Pat your fish dry with a cloth or paper towel. Then, season both sides of the fish with salt and pepper, to your liking.
Prepare your breading mixture in a large flat bowl or plate. Mix in any optional add-ins.
Coat the fish fillets in oil. I like to use avocado oil. You can also use canola oil, vegetable oil, or olive oil. *For even crunchier fish, coat the fish in the beaten eggs instead of the oil. Then coat the fish with the breading mixture.
Coat each fish fillet on both sides in the breading mixture.
Preheat the air fryer to 400°F for 5 minutes. Then add the fish fillets in a single layer to the air fryer and cook for 10-12 minutes, flipping halfway through. If you'd like to get a particular side more crispy, cook for an additional 1-2 minutes.
Serve with your favorite sides and enjoy!