• 1 tbsp Sichuan peppercorns
• 50 g 2 oz) cornflour
• 1 tbsp sea salt
• 400 g 14 oz) large raw peeled prawns
• 200 g 7 oz) fine green beans
• 60 ml 2 fl oz) vegetable oil
• 2 thumb-sized red chillies, sliced
• 2 garlic cloves, thinly sliced
• 4 spring onion (scallions), cut into 5 cm (2 inch) lengths

Crispy Chilli Sauce

• 2 tsp cornflour
• 2 tbsp roasted chilli flakes in oil, drained
• 2 tbsp black vinegar
• 2 tbsp light soy sauce
• 1 tbsp hoisin sauce

• steamed rice, to serve

In a small frying pan, heat the Sichuan peppercorns until fragrant, about 30 seconds. Roughly grind in a spice mill or mortar and pestle and then mix in a shallow bowl with the cornflour, sea salt and a good grinding of black pepper.

Use a sharp knife to slice down the back of each prawn and rinse out the vein. Toss the prawns in the spicy flour and coat well. Shake off excess.

To make the crispy chilli sauce, first dissolve the cornflour in 1 tablespoon water, then in a small bowl combine with all the other ingredients.

Blanch the beans in boiling water for 1 minute, then rinse under cold water and drain.

Add the vegetable oil to the wok and fry the chilli and garlic until golden, about 1 minute. Remove from the pan. Add the prawns and fry until pink and slightly curled.

Drain off almost all the oil and add the beans to the wok along with the spring onion. Stir-fry for 1 minute and then add the sauce. Keep stir-frying until warm and sticky, about 1–2 minutes.

Remove the stir-fry from the heat and serve with steamed rice. Sprinkle with the fried garlic and chillies.