This sweet and sour prawns recipe is Chinese restaurant classic. The homemade sauce and butterflied prawns (still in their shells) take less than half an hour to cook. Serve with some simple steamed rice on the side, to turn this into fantastic meal.

1. For the sauce, mix all the ingredients together and set aside.

2. Butterfly the prawns with a pair of scissors. Starting from the top between the head and the body, cut down the spine of prawn all the way to the tail. Once the shell is opened up, run a sharp knife through to butterfly the prawn further. Press the two sides of the prawn down to butterfly completely. Slice horizontally 6-8 times along the meat of the prawn, as if scoring it, without cutting through the shell underneath.

3. Place the butterflied prawns into a bowl and add the cornflour, mixing well until slightly creamy.

4. Preheat a deep fat fryer to 180°C. You can also use a wok or large pot filled no more than halfway with oil – to check the temperature dip in the tip of a wooden chopstick or skewer. It's ready when it starts to fizz after a second in the oil.

5. Carefully place the prawns into the oil.

6. Deep-fry for 2–3 min until crispy.

7. Remove carefully with a slotted spoon and drain on kitchen paper.

8. In a separate wok, heat 1 teaspoon of vegetable oil over a high heat until smoking. Add the onion and stir-fry for 1 minute until the onions are lightly browned, pour over the sauce and bring to a boil

9. Once boiling, add the prawns and toss through a few times to mix everything together. Serve immediately with a garnish of dried pineapple and coriander leaves. If you can't find dried pineapple in the shops, you can make this yourself by placing 12 slices of pineapple on a lined baking tray in an oven at 40°C overnight.

Enjoy!