Flatten chicken breasts to about ½-inch thickness between sheets of wax paper, then cut into 3 equal pieces.
Whisk together skim milk and hot sauce in a small bowl.
Marinate chicken pieces in the milk mixture in a sealed bag in the refrigerator for 4 hours to overnight.
Preheat oven to 400°F and coat a baking sheet with nonstick spray.
In a food processor, pulse ½ cup cornflakes with paprika, salt, and pepper to form crumbs. Mix with panko in a shallow dish.
Crush the remaining ½ cup cornflakes by hand and mix into the panko mixture.
Coat chicken pieces with the cornflake mixture and arrange on the baking sheet.
Bake at 400°F for 15 minutes, then reduce temperature to 350°F and bake for an additional 5-10 minutes until crispy and cooked through.