What can I say about the Underground Butcher? I've been there once, but I will return because the quality of the food was something to behold.
I ordered the pork belly sandwich, and it was just porky goodness. The salty richness of the pork belly encapsulated in a warm baguette with great crust and awesome chew really created an above average sandwich. Not to mention, the Pork Belly sandwich also had pork liver mousse spread and pickled apple slaw. Those condiments enhanced the sweet and savory flavors of the sandwich. It's that great composition with quality ingredients that make this neighborhood store a great stop.
Side note: Buy the charcuterie... Its's delicious. Take it home with some awesome cheese and a few baguettes, and then open a nice bottle of wine, and at that moment, you might just have found a little piece of heaven.