Salpicón de marisco

Name: Salpicón de marisco
Ingredients: 750g mussels in their shells; 50ml sherry; 1 garlic clove, sliced; 1 bay leaf; ½ red onion, finely chopped; ½ green pepper and ½ red pepper, both cut into 1cm chunks; ½ cucumber or 2 small Lebanese cucumbers, halved lengthways, deseeded and cut into 1cm chunks; 3 tomatoes, quartered, deseeded and chopped; 300g cooked king prawns, shelled and deveined; 2 tbsp flat-leaf parsley, chopped; sweet smoked paprika, for sprinkling; 150ml extra virgin olive oil; 50ml sherry vinegar; ½ tsp sugar