The type of vegetables you use doesnt really matter - just choose a variety of colours, flavours and textures. Tempura batter: The ingredients should be as cold as possible and the batter must be made immediately before using. It should be light, crisp and almost transparent. Chill water and egg in freezer until almost slushy. Whisk egg, salt and water until light and very frothy. Whisk in flour a little at a time keeping the batter foamy. Give it a splash of soda and a final whisk before use. Dip the vegetables and prawns in the batter and deep fat fry a few at a time. Serve immediately, on pretty plates with a hoi sin dip served in individual butter pots. Dipping sauce: Put all ingredients in a pan with 2tbsp water and simmer together to make a hot sweet sauce. Add more water if it is too thick to dip. Season with salt, pepper and a pinch of sugar if needed.