Best posh breakfast in London?

I need something to cheer me up. Recommendations?

Yep I recommended Delamina but never done breakfast there.

45 Jermyn Street behind Fortnums is v good for a posh breakfast and quieter than the Wolseley. 

The Guinea 'All grills come with sausage, bacon, fried egg, mushroom, tomato and onion'.

That's the spirit.