The Oh Boy sauce looks like mayo, and has a similar consistency. It does not taste like mayo though! I can not even begin to calculate what they use to flavor this condiment, but it is a mighty fine burger topping.
Even without the lettuce the Bernieburger is quite messy and a trick to handle. Having the BBQ sauce on the bottom may add to this by somewhat soaking through the fresh bun, but the flavor made up for all it. An very tasty flavor combination where you can actually taste the beef, the bacon, the sauces and the onions, all combining together.