01 - Pat squid rings dry thoroughly using paper towels.
02 - Whisk together flour, cornstarch, baking powder, salt, and black pepper in a large bowl.
03 - Gradually add cold sparkling water to dry ingredients, whisking until smooth and slightly thick.
04 - Heat vegetable oil to 350°F (180°C) in deep pan or fryer.
05 - Dip squid rings into batter, letting excess drip off, then fry in batches for 2–3 minutes until golden and crisp. Avoid overcrowding.
06 - Remove fried squid with slotted spoon and drain on paper towels. Sprinkle immediately with salt.
07 - Serve hot with lemon wedges and optional chopped parsley.