Baked cod on pea puree with beurre blanc sauce

Now here's something a little bit different for Jenny Eatwell's Rhubarb & Ginger - a fish dish! We really enjoy eating fish.  Let me say that straight away.  However (and you knew one of those was coming, didn't you?), we just don't get the opportunity very often.  Which is completely ridiculous, considering that a) we live 2 minutes (literally) from the sea and b) we'll