01 - Pat squid dry using paper towels. Toss squid rings with soy sauce, garlic powder, white pepper, and salt in a bowl. Let marinate for 10 minutes.
02 - Combine flour, cornstarch, and baking powder in a mixing bowl. In a separate bowl, beat the egg with cold sparkling water. Pour wet mixture into dry ingredients and whisk until loosely combined; batter should be slightly lumpy.
03 - Heat vegetable oil to 350°F (180°C) in a deep pan or fryer.
04 - Dip marinated squid rings into the batter, allowing excess to drip off.
05 - Fry squid in batches for 2 to 3 minutes until golden and crispy. Avoid overcrowding the pan.
06 - Remove fried squid using a slotted spoon and drain on paper towels. Serve immediately with lemon wedges and desired dipping sauce.