Place popcorn, mushrooms, onion powder, garlic powder and salt in a blender (or food processor) and blend until powdery and almost smooth; pour into a wide, shallow bowl.
Beat egg in a shallow bowl; set aside.
Heat oil in a large, non-stick skillet over medium-high heat. Dip tilapia into egg and then into popcorn mixture, coating both sides. Cook tilapia about 3 minutes per side or until fish is golden and center is cooked. Serve with lemon wedges.
Variation: Substitute boneless, skinless chicken breasts for tilapia and adjust cooking time as needed.
Recipe compliments of the Popcorn Board