I can't blame people being lousy at physics and chemistry, but
trying to imitate food cooked by the professionals is a darn
difficult task. What you are mentioning is the texture of the food
which is determined by the formation of the coating protein. Of
course, that is determined by the temperature of the food being
cooked. Firstly, did you seperate the cooking of the meat and the
sauce? The meat is deep-fried and sauce stir-fried. Make sure temp
of the deep fry is 175 to 190 degrees centigrade, while the
stir-fry is 100 deg cent thereabouts. Slide the battered meat into
the deep fry for 2 mins or thereabouts. Scoop up and note this,
dump them on top of a oil strainer with ice cubes. This allows the
protein to form to a bigger amount and hence greater texture and
crunchiness. Serve up with the sauce. Hope you don't need me to
provide the sauce recipe. If you prefer a lighter taste, use
potatoe starch flour for the batter mix.