Combine 1 cup crushed cornflakes with 1/2 teaspoon paprika, 1/2 teaspoon garlic powder, 1/2 teaspoon onion powder, 1/4 teaspoon salt, 1/4 teaspoon pepper, and optional cayenne in a shallow bowl.
In a second bowl, whisk 1 egg with 1/2 tablespoon milk and optional 1/2 tablespoon Dijon.
Dip each 1/2-pound batch of chicken tenders in the egg mixture, let the excess drip away, then press firmly into the seasoned cornflakes.
Preheat the air fryer to 375°F for 3 minutes and lightly spray the basket. Arrange the tenders in one layer and lightly spray the tops.
Air fry at 375°F for 10 to 13 minutes, flipping halfway, until deeply golden and 165°F inside. Rest 2 minutes before serving.