When I planned the menu for Caroline’s birthday party, these bars were something of an afterthought.  They helped round out the dessert portion of the menu, adding another berry treat for our little berry fiend.  I suspected they would be good but oh.my.gosh, people, these were definitely the highlight of the spread.  The buttery, crumbly crust with a hint of lemon and the amazing blackberry filling are an irresistible combination.  These bake up very thick, so you can cut them on the small side.  The recipe doubles easily in a 9 x 13-inch pan to feed a larger crowd.  This recipe will undoubtedly become a total staple for bringing to spring and summer parties, potlucks, and more.  I’m looking forward to trying it with other fruits as well.