Where do you add the additional grated or minced clove of garlic?

Hopefully you get the answer from the author. When I make RB&R, I add in minced garlic near the end of the cooking process to add a more pronounced garlic flavor. Garlic tends to mute out in long cooking, and become part of the flavor background. So adding in a bit of minced garlic at the end helps counter that. I'd add it in this recipe when you add in the pureed part to the rest of the beans, and simmer for a few minutes. That will get the bitter bite off, but leave a pleasant garlic taste.