If you can work Lady Gaga into a conversation about Texas barbecue, then it's probably going to be a pretty good conversation. That was true Thursday morning when I stopped by Aaron Franklin's new place in Austin on my way back to Dallas. It was just after 9 a.m., still about two hours until he opened for business, so Franklin had a few minutes to show me around. "What are you doing in town?" he asked. I explained that I had gone to the Lady Gaga concert the night before at the Erwin Center. (Terrific show, btw.) One of her…