How to display date in a very unique way

I’m currently using Textpattern (openswitch.org) and you can see how I’ve got my date splayed down the side of the post. The code I use to do this in Textpattern (via some help on the Textpattern forums):

<?php echo nl2br(chunk_split(posted(array('format' => '%m%d%y')), 1, "\n")); ?>

In Textpattern the date posted data is called with the “posted” and is formatted with the “format”. How would I accomplish this same thing in WordPress? If I could figure this out I’d switch my blog from Textpattern to WordPress but when I try to simply swap out the “posted” for something like “date_posted” it doesn’t work so I assume I’m doing something very wrong.

Any help would be greatly appreciated.