1 avocado, peeled and stone removed, diced
4 red chillies
1 guajillo chilli, toasted
100²µ/3Β½΄Η³ϊ cucumber, peeled
1 tbsp finely chopped fresh dill
2 tbsp finely chopped fresh coriander
2 garlic cloves
6 limes, juice only
1 red onion, thinly sliced
1 tbsp Worcestershire sauce
100ml/3Β½fl oz olive oil
Β½ tsp Mexican oregano
500g/1lb 2oz pearl barley
20²µ/ΒΎ΄Η³ϊ butter
4 sushi grade carabinero prawns, peeled, halved and de-veined (head reserved)