2 c. ice water
1 2/3 c. all-purpose flour
1 egg
1/8 tsp. baking soda
1/8 tsp. salt
1/8 tsp. cayenne pepper

Mix all ingredients in blender until smooth. Pour into bowl. Heat oil in heavy deep skillet to 400 degrees. Dredge shrimp in flour. Dip in tempura batter. Place in oil and cook until golden brown, 1/2 to 2 minutes.