How to Make It
Whisk together ketchup, hot sauce, and egg white in a small bowl until smooth. Place panko in a large bowl. Toss together cauliflower florets and ketchup mixture in a second large bowl until coated. Working in batches, toss cauliflower in panko to coat. Coat cauliflower well with cooking spray.
Place half of the cauliflower in air fryer basket, and cook at 320°F until golden brown and crispy, about 20 minutes. Repeat with remaining cauliflower.
While cauliflower cooks, stir together sour cream, blue cheese, garlic, vinegar, and pepper in small bowl. Serve cauliflower with blue cheese sauce.