1.Combine cornflour, egg white, water and salt. Add prawn; toss to coat. Set aside 10 minutes.
2.To make Szechuan sauce: combine all ingredients.
3.Heat half of the peanut oil in a wok on high. Stir-fry sugar snap peas 2 minutes, until bright green. Remove; set aside.
4.Cook prawns in remaining oil for 2 minutes, until opaque. Remove.
5.Stir-fry onion and ginger for 10 seconds. Return prawns with sauce; stir-fry 30 seconds. Toss through sugar snap peas. Serve with rice and green tea.