Place prawns in a bowl and add combined ingredients (A). Toss to mix then leave aside for five to 10 minutes.
Just before deep-frying toss the prawns in corn flour. Heat oil in a large saucepan over medium heat until hot. Fry the prawns in batches for two to three minutes or until cooked through. Dish out and drain on absorbent paper.
Heat wok with sesame oil, sauté garlic and ginger until aromatic. Add ingredients (B), dragon fruit and spring onion. Return prawns to the saucepan and toss briefly to combine.