2. Mix ketchup with Worcestershire sauce, some water, a little bit dark soy sauce, mix well.
3. Devein the prawn with a toothpick, remove the sharp from the prawn head and cut out the legs. Cut the bottom of the prawn alongside, then deeply cut.
4. Fry ginger until and white part of the scallion until fragrant. Put prawn in pan to fry, flip. Season with some salt, keep frying until the prawn is golden brown, take out.
5.Turn to low heat, put crushed sugar in pan, then pour the sauce in, simmer until sugar dissolves. Put the prawn back, add some green part of spring onion. Cover, cook over medium high heat for 1 min.
6. Cover, thicken the sauce with starch slurry. Off heat, serve hot.