I don't think I'll take a chance on eating these :-X
It's a Peziza, but I'm not sure which one. There's nothing in my books about edibility, but it certainly doesn't look appetising!
A couple of the Peziza's are poisonous, but most seem to be inedible. In my book, for one of the poisonous ones - if it is cooked, the poison is gone and it is edible!
For a really good website/forum for fungi (and British flora/fauna) identification - try http://www.wildaboutbritain.co.uk/forums/