Wash and cut the onions in half, then slice them into thin pieces.

Cut the carrots into thin slices.

Chop the green onions into small pieces.

In a mixing bowl, combine 120g of all-purpose flour, 30g of corn starch, 1 tbsp of onion powder, 1/3 tbsp of garlic powder, 1/3 tbsp of salt, and 1/2 tbsp of baking powder.

Gradually add 180ml of sparkling water to the dry ingredients, stirring until the batter is smooth. The sparkling water helps make the batter extra crispy. If you don't have sparkling water, you can use ice water instead.

Heat the cooking oil in a deep frying pan or pot to a medium heat (170℃-180℃ or 340°F-355°F).

To check if the oil is hot enough, drop a small piece of batter into the oil. If it floats and sizzles, the oil is ready.

Coat the vegetable slices in the batter. You can use a spatula or a small strainer to dip the vegetables into the batter and shape them.

Carefully place the battered vegetables into the hot oil. Do not touch them until they float to the surface.

Fry the vegetables for 5-8 minutes until they are golden brown. Remove them from the oil and let them drain on paper towels.

For extra crispiness, fry the vegetables a second time for an additional 3-5 minutes.

In a small bowl, mix 2 tbsp of mayonnaise, 1 tbsp of Sriracha sauce, 1/2 tbsp of sugar, and 1 tbsp of lemon juice until well combined.

Serve the super crispy fried onions and vegetables hot with the Sriracha mayonnaise sauce on the side.