01 - Slice chicken breasts into thin strips measuring 1/2 x 2 inches. Pat thoroughly dry with paper towels and season evenly with salt and pepper.
02 - Whisk together flour, cornstarch, and baking powder in a mixing bowl until fully combined.
03 - Lightly beat the egg in a separate bowl, then incorporate the ice-cold sparkling water.
04 - Pour the wet mixture into dry ingredients. Stir briefly with chopsticks or fork, leaving batter slightly lumpy—avoid overmixing to maintain crispiness.
05 - Heat vegetable oil in deep pan or fryer to 350°F.
06 - Dip seasoned chicken strips into batter, allowing excess to drip off, then carefully place into hot oil.
07 - Fry in batches for 3-4 minutes until golden brown and crisp, turning once mid-cooking. Avoid overcrowding the pan.
08 - Transfer cooked chicken to wire rack or paper towels to drain excess oil.
09 - Combine soy sauce, mirin, rice vinegar, sugar, and ginger in small saucepan. Heat gently until sugar dissolves, then cool to room temperature.
10 - Plate chicken tempura immediately while hot, accompanied by dipping sauce on the side.