Japanese Very Light Tempura Batter

Ingredients

 * 1 egg
 * 1 cup very very cold water
 * ⅛ teaspoon baking soda
 * ¾ cup all-purpose flour or tempura flour (3 oz)

Directions

 * 1) Break the egg into a bowl containing the iced water and whisk until frothy.
 * 2) Add baking soda and flour.
 * 3) Beat until the flour is just mixed in.
 * 4) Do not over beat.
 * 5) Batter should be so thin that the merest wisp clings to the vegetables dipped in it.
 * 6) If it seems too thick, add a little more iced water, and keep the batter cold.