Place the grated zest in a food processor with the fennel, garlic, onion, capers, herbs, a good glug of olive oil and seasoning, and blitz until finely chopped. Pack the mixture into the fish and ...
Carefully lift the remaining two fillets onto the plate. Coat with the herb butter and surround with the potatoes, onions and fennel, which should be deliciously charred at the edges. Serve ...