Mix all purpose flour and water in a bowl and keep aside.
Mix crab meat, cream cheese, spring onion greens, soy sauce, fish sauce, garlic, white pepper powder, sesame oil, cayenne pepper and salt in another bowl.
Lay a wonton wrapper on the work surface.
Apply the flour and water mixture on all the sides.
Keep small portion of crab filling in the center and bring the ends together to make a triangle.
Again apply some flour and water mixture on the closed end and bring the ends together to fold the wonton.
Make all the rangoons in the same manner.
Heat oil in a pan.
Deep fry the rangoons till golden brown.
Drain on a plate lined with kitchen tissue.
Serve immediately with some sweet and spicy sauce.
While making the Rangoon, make sure that there is no air inside, otherwise it will break open while frying. Keep the inside sealed and fold the wonton sheet into four cornered square. Make sure the oil is neither too hot nor too low. As the low temperature oil can make your wontons oily, and the very high temperature might burn them. If you are baking the these, make sure you have brushed them properly with oil.