BBC Food - Recipes - Chicken croquetas with piquillo pepper mayo

Ingredients

• 75g/3oz butter
• 200g/7oz plain flour
• 500ml/18fl oz milk
• salt and freshly ground black pepper
• 75g/3oz fresh breadcrumbs
• 150g/5oz cooked chicken , chopped
• 1 small bunch fresh tarragon , leaves picked and chopped
• 75g/3oz plain flour
• 2 free-range eggs , beaten
• 75g/3oz panko Japanese breadcrumbs
• 50g/1¾oz ground almonds
• rapeseed oil , for deep frying
• 1 large bunch watercress , to garnish
• 3 free-range egg yolks
• 1-2 tsp English mustard
• 100ml/3½fl oz rapeseed oil
• 1 tbsp white wine vinegar
• 75g/3oz piquillo peppers , roughly chopped
• 1 tbsp flatleaf parsley , roughly chopped