Whisk together vinegar and red pepper flakes; whisk in oil. Reserve.
Combine chicken, bell pepper and green onion; fold into reserved dressing.
Deep fry rice sticks in hot oil in 2 batches for about 3 seconds; turn, then fry another 3 seconds. Drain well.
Dice avocado; gently fold into chicken salad.
Break up fried rice sticks on serving plate. Mound salad on top of rice sticks. Garnish with green onion.