• Prepare the shrimp by deveining them (if necessary) and removing the shell up to the tail. Make 4-5 small notches on the “belly” of each shrimp and stretch them out. Pat them dry with paper towels.
• In a bowl, whisk together ½ cup of the flour, water, and egg whites. In a second bowl, add the remaining flour.
• Place cornstarch and salt in a plastic zipper bag. Add shrimp and toss well to coat.
• Preheat the air fryer to 370 degrees F for 5 minutes. Spray the inner basket generously with cooking oil spray.
• Dip shrimp, one at a time, in the wet flour batter, then dredge them through the dry flour to lightly coat them. Place them on a clean plate or parchment-lined baking sheet. 
• Working in batches, set the shrimp in the basket in a single, uncrowded layer. Spray them well with cooking oil spray, then air fry for 7-8 minutes, until lightly golden.

FROM FROZEN:

• Prep shrimp through step 5, then place the plate or baking sheet in the freezer for 1 hour to flash-freeze. Remove the shrimp and store in a plastic zipper bag until ready to cook.
• When ready to cook, preheat the air fryer to 370 degrees F for 5 minutes. Spray the inner basket with cooking oil spray.
• Working in batches, set the frozen shrimp in the basket in a single, uncrowded layer. Spray them well with cooking oil spray, then air fry for 12-15 minutes, until lightly golden.