In a small saucepan, combine water, soy sauce, mirin, and sugar. Bring to a boil over medium heat, then reduce the heat and simmer until the sugar has completely dissolved. Remove from heat and set aside.
¾ cup water, 3 tablespoons soy sauce, 2 tablespoons mirin, 2 teaspoons sugar
In a large bowl, whisk together the flour, cornstarch, and salt. Create a well in the center, then pour in the water and egg yolk. Stir until just combined—the batter will be lumpy. Gently fold in the egg whites.
1 cup all-purpose flour, 2 tablespoons cornstarch, 1 pinch salt, 1 cup iced water, 2 large egg whites
Dip one shrimp at a time into the batter, making sure to coat them well.
1 pound medium shrimp
Once three shrimp are battered, arrange them in the air fryer basket.
Air fry the shrimp at 160ºC (320°F) for 8 minutes.
Repeat the process with the remaining shrimp, battering a few at a time while the previous batch fries.
Serve warm and enjoy!