I had a whole post written about this, but there's nothing else to tell you that the title hasn't already. Brown butter. Bourbon. Streusel. (The bananas are not the important part here).
Fine. I'll try to tell you more. Brown butter and bourbon are BFF's. They totes gave each other best friend necklaces when they were in first grade and they both still have them. Sometimes I smell bourbon and think, "hmmm...smells brown buttery".
This bread. Oh, this bread. None of the components will jump up and punch you in the face. Except maybe the streusel, but that's just the way a streusel laced with big flakes of salt is in anything. As an added bonus for people who don't like bananas (aka me), the bourbon and brown butter mask a lot of the more...unpleasant flavors. Instead, its oh so subtley banana, but a major punch of nutty caramelly-ness.
Jeeze...I'm drooling again. I tried. I can't talk about this anymore. Just do it.