With a sharp knife, make five shallow slits across the underside of each shrimp. Next, flip the shrimp over so their undersides are resting against your cutting board
Gently press down on the shrimp with your fingers to flatten slightly. This will stop the shrimp from curling when being fried. Don't press to hard that you may break the shrimp into pieces instead. Set aside
Beat one egg and water in a bowl. Mix well and then slowly mix in the 2 cups flour until just combined, but not to over mix, you don't want a smooth batter, in fact you want to see lumps of flour to remain in the batter
Preheat your oven to 200 F. Preheat a deep skillet with vegetable oil for deep-frying until the temperature is about 350 F or you can try dropping few drops of the batter and if they sink down and then puff up and rise to the top, the oil is ready
Dip the shrimp into the tempura batter, and carefully place in the hot oil. Don't overcrowd your skillet. Work in batches if needed. Cook the shrimps for about 4 minutes. When you notice bubbles that appear on the surface of the oil getting smaller and decreasing, and see the ingredients float to the top, you'll know your shrimps are done. The color will be a light golden brown- so make sure they aren't overcooked and turned dark brown instead
Transfer the ingredients from the oil and rest on a cooling rack to let the oil drip and slip them into the oven while working on the rest