I had never head of Charnushka or Nigella seeds until ITJB so, being the curious type, I ordered some ... and now I'm hooked!

What a wonderful surprise.  These little seeds that look like undersized black sesame taste of black pepper, thyme, onion and I don't know what else.  They are wonderful on top of rolls.  I got some cheaply from www.myspicesage.com [1] but I'm sure other places like Penzey's have them.

Glue them on with egg wash and it's a great way to perk up a plain chewy roll.