Heat oven to 200C/180C fan/gas 6. Lay
fish, skin-side-down, in an ovenproof dish.
Season, dot with butter and pour over the
wine. Place fish in the oven for 10 mins until
just cooked, then lift onto a warm plate.
Working very quickly, pour the juices
from the dish into a small saucepan
with the crème fraîche, boil until slightly
thickened, then stir through the sorrel
until just wilted. Spoon over the fish
before serving. Buttered new potatoes
on the side are a must.