Kung po prawns - Good Food Middle East

Ingredients

• 1 tsp cornflour
• 2 tbsp light soy sauce
• 400g large raw prawns, frozen is fine, butterflied (see tip, below)
• 2 tbsp Chinese rice vinegar
• 1 heaped tbsp tomato purée
• 1 tsp caster sugar
• 2 tbsp sunflower or groundnut oil
• 85g unsalted, roasted peanuts
• 6 small or 3 large whole dried chillies
• 2 x 225g cans water chestnuts, drained
• thumb-sized piece ginger, finely grated
• 2 garlic cloves, finely chopped