Any guides out there for "How-To: ROM baking!"

[Gr8hifi]

There's quite a few awesome ROM's floating around now and that's cool. I know that Lego ROM is the "kitchen" for the layman but I was wondering if there were any guides out there for rolling your own? I used to do my own "baking" back in the Windows Mobile days and there were a few good guides for getting going with that. Anybody around here seen one for the Optimus ROM's? (or any other android ROM's for that matter).