Prep the cauliflower. Rinse and dry the head of cauliflower thoroughly.
Cut into small, popcorn-sized florets—about 1-inch pieces—so they cook evenly and crisp well.
Preheat the air fryer. Set it to 400°F (200°C) for 5 minutes. A hot basket jump-starts crisping.
Make the dry mix. In a bowl, combine panko, Parmesan (if using), 1/2 teaspoon salt, 1/4 teaspoon pepper, and half of the paprika and garlic powder. Stir to mix.
Make the seasoning base. In a separate large bowl, whisk eggs with cornstarch, remaining paprika, garlic powder, onion powder, chili powder (if using), 1/2 teaspoon salt, and remaining pepper.
The cornstarch helps create a light crust.
Coat the florets. Toss the cauliflower in the egg mixture until evenly coated. Work in batches: shake off excess, then roll each floret in the panko mixture to cover all sides.
Oil and arrange. Lightly spray the air fryer basket. Arrange coated florets in a single layer with space between them.
Lightly mist the tops with oil for extra crunch.
Air fry, flip, finish. Cook at 400°F (200°C) for 10–12 minutes, flipping halfway. They’re done when golden brown and crisp outside and tender inside. Very small pieces may finish around 9 minutes; larger ones may need up to 14 minutes.
Season and serve. Sprinkle with a pinch of salt while hot.
Serve immediately with your favorite dipping sauce.
Batch cooking tip. If cooking multiple batches, keep finished pieces on a wire rack in a low oven (200°F/95°C) so they stay crisp.