In a small bowl, mix the flour with the chili powder, garlic powder and salt. Place the beaten egg in another bowl and the panko breadcrumbs in a third bowl.
Dredge the avocado in the flour mixture, then the egg and finally the panko breadcrumbs, pressing down lightly until the crumbs stick. Spray both sides with oil.
For the air fryer, air fry at 400°F. until about for 7 to 8 minutes, turning halfway through until golden brown.
For the oven, bake on a greased baking sheet lined at 425°F for 12-15 minutes, turning halfway through, until golden brown.
Serve hot with spicy mayo dipping sauce, if desired.