1Butterfly the prawns along the back without cutting all the way through, coat both sides with cornstarch, then gently pound with a rolling pin until thin.
2Bring a pot of water to the boil, then add the ginger, spring onion, and Chinese cooking wine.
3Add the prawns in small batches, boil for about 2 minutes or until cooked through, then drain well.
4Heat the oil in a wok and stir-fry the jalapeño and garlic until fragrant.
5Stir in the sugar, salt, oyster sauce, and soy sauce, then add the cherry tomatoes and immediately turn off the heat.
6Pour the sauce over the prawns and gently toss to coat.