Remove the intestines, put shrimp in a bowl. Mix in the ingredients mentioned above. Marinate for 30 minutes.
For the dough, beat the egg whites until stiff. Fold in the flour and cornstarch and stir to form a dough.
Put all the ingredients for the sauce in a saucepan and bring to the boil. Simmer over a low heat for 10 minutes. Remove the prawns from the marinade and dip in the batter.
Heat the oil and deep-fry the prawns for 3-4 minutes. Garnish and serve with the sauce.