For the dressing: Combine the chili, oil, lime juice, fish sauce, sugar, ginger and sesame oil in a bowl and mix well.
Add the shrimp, sugar snap peas and mango and toss together well. Chill in the refrigerator for 20 minutes.
Serve the sweet and sour shrimp on the lettuce with the sesame seeds in a small pot or bowl for dipping.
Recipe courtesy of Ching-He Huang