Rainbow trout Grenobloise

INGREDIENTS

• 400g/14oz Jersey Royal potatoes
• 2 tbsp extra-virgin olive oil
• 2 tsp chopped fresh flatleaf parsley
• salt and freshly ground black pepper
• 2 x 250g/9oz rainbow trout
• 4 pinches sea salt
• 2 pinches freshly ground white pepper
• 40g/1½oz unsalted butter
• 4 tsp water or brown chicken stock
• ¼ lemon
• 1 tbsp capers
• 1 tsp chopped fresh flatleaf parsley
• 30g/1oz white bread