Add the breadcrumbs (panko) and Old Bay Seasoning to a shallow dish. In another bowl, add your egg, and beat the egg with a fork.
Use paper towels to remove excess moisture from the fish. Dip your fish into the egg on both sides and then dip it into the breadcrumb mixture. Repeat with the remaining fish.
Spray the air fryer basket with cooking spray, or line the air fryer basket with parchment paper. As you bread your fish, place them into the greased basket in a single layer. Spray the breaded fish with cooking spray, or brush with olive oil, which will help crisp the breadcrumbs up.
Set the temperature to 350 degrees F, air fryer setting, set the cooking time for 12-15 minutes, flip the fish halfway, and then respray the fish with cooking spray.
Check the internal temperature before removing the fish, which should have a 145 degrees F reading. Remove the fish when it’s fully cooked. (Cooking times are to depend on what air fryer you own and how thick your fish is)
Add your hamburger rolls to the air fryer basket, and air fry for 2-3 minutes at 320 degrees F; remove once toasted.
Assemble the sandwich, place the tartar sauce on the bottom bun's bottom, then place the Crispy Fish Fillet on top, add a piece of American Cheese, and cover with the top bun. If you want to melt your cheese, add the sandwich back into the air fryer and cook for another 1-2 minutes until the sandwich has melted cheese.
Plate, serve, and enjoy!