Remove shrimp heads and outer shell, while making sure to keep the tail.
For the tempura: Beat the egg with water, add gradually the flour, corn flour, mustard, yeast and the salt. Whisk together until smooth.
Make sure the temperature of the oil is hot.
Dip each shrimp in the tempura mixture, add salt and pepper to taste and slowly plunge the shrimp in the frying oil. Cook until the breading is golden. Remove the shrimp from the oil and place onto a sheet of paper towel to absorb excess oil.
Use vegetables or minced chicken in the batter - guaranteed success!