In a bowl, place chicken, cayenne, black pepper, salt, cornstarch and egg white. coat chicken well. In large frying pan, saute chicken in oil until well browned. remove chicken and add to the pan, onions, garlic, and jalapenos. saute for 5 minutes. add mushrooms, vinegar and sugar. saute for 4 minutes. add cooked chicken and stir. saute for 3 minutes. serve over cooked noodles.