http://www.nytimes.com/2006/11/08/dining/081mrex.html
I wish I could say I found this article on my own, but I had two friends (HangerMike & DragonCoder) send me links to it because they knew my passion for baking.
This requires a 5 quart dutch oven, but a quick search of eBay for "Cast Iron Enamel Dutch Oven" will yield several in the $30-$50 range.
Here is a video of his technique: http://www.youtube.com/watch?
-Matt the Weekend Baker