1lb/450 g medium raw prawns, thawed if frozen
3/4 teaspoon of salt
2 teaspoons of conrflour
1 egg white beaten
2 oz/50g pork fat, minced
8 water chestnuts
7 slices of white bread, with crusts removed
4oz/100g white sesame seeds
vegetable oil for deep-frying
Peel and devein prawns, cut a 1/4 inch (5mm) deep slash along the back of the prawns and remove black veins. Pull of heads, pat dry with kitchen paper and mince in a food processor. Transfer to a bowl, add salt, cornflour and egg white, and stir vigorously for 2 minutes. Add pork fat and water chestnuts and mix throroughly. Refrigerate for 1/2 hour.
Spread paste onto bread slice. Spread sesame seeds on a dish and press slices paste-side down to coat.
Half-fill a wok with oil and heat to 180C/350F. Fry paste side down for 1 1/2 minutes, then turn over and fry until bread is golden brown. Remove and drain on kitchen paper. Cut each slice into 4 strips and serve.