Ingredients:

  Amount  Measure       Ingredient -- Preparation Method
--------  ------------  --------------------------------
     1/2  cup           flour
   1      tablespoon    cornstarch
   1      teaspoon      baking powder
     1/4  teaspoon      salt
   2                    egg whites
     1/2  cup           beer
                        peanut oil for deep frying

Preparation:

Make the tempura batter by whisking flour, cornstarch, baking powder, salt in a medium bowl and whisking in egg whites and beer. Let sit in the refrigerator about 30 minutes. Pour peanut oil into a deep saucepan to the depth of about three to four inches and heat on high until a bread cube dropped into the oil immediately sizzles.