ROAST FREE-RANGE DUCK WITH BLACKBERRY SAUCE INGREDIENTS 2½ kg free-range duck sea salt flakes and freshly-ground black pepper 2 Tbsp extra virgin olive oil ¼ cup caster sugar 50g unsalted butter ¼ cup sherry 1 Tbsp raspberry vinegar juice of 2 oranges 1 cup chicken stock 2 cups blackberries 2 Tbsp brandy 2 Tbsp maple…