Devein the shrimp and remove the shells right up to the tail. Make shallow slits into the inner and outer parts of each shrimp to straighten the shrimp, and pat them dry to remove the moisture.
Dust cornstarch over the shrimp. In a medium-sized pot, heat the oil to 350ºF. Prepare the batter. Sift the flour, add cold egg and cold water to the flour. Mix carefully with a whisk, don't overmix.
Add the shrimp to the batter bowl and holding it by the tail, place it in hot oil.
Fry the shrimp for about 2 minutes until golden brown. Repeat with all shrimp.
Notes
The nutritional information is an estimate, as the precise calculations will depend on the amount of oil your shrimp absorb when fried.