1. For the gochujang chilli sauce, add all of the ingredients to a saucepan and simmer for five minutes until the sauce thickens slightly. Tip into a bowl and set aside to cool.

2. Preheat the barbecue grill until hot.

3. Using a sharp serrated knife, butterfly the prawns by slicing lengthways through the back of the shell, including the head, until you can open them out flat – you could also cut the shell with a pair of kitchen scissors and open the tail out with a knife. Remove the intestinal tract and wipe out the heads with paper towel. Brush with oil and season lightly.

4. Grill the prawns for one minute, flesh-side down, flip and grill until just about cooked. Remove the prawns from the barbecue and brush with the chilli paste. Squeeze over some lime, sprinkle with spring onion and sesame seeds, and serve with the snow pea tendrils (if using).

Tips

1.  Take the prawns off the grill just before they're completely cooked; they'll finish cooking by the time you've plated up and you'll avoid powdery meat.

2.  Firm the prawns in the freezer for 30 minutes to make them a little easier to handle when you butterfly them.

3. The sauce can be made ahead, and it's also delicious on whole grilled fish or as a chilli condiment with almost endless uses.