Butter piecrust gets crunchy on bottom and edges of cast iron skillet, with dough pieces in layers with the berries and sugar. Found this in Southern Living a number of years ago, but I don't have the man's name to give him credit. You can use peaches or blueberries as well, blackberries are just my favorite. I have given up picking my own blackberries so now harass the people at the farmer's market until they get some. Frozen fruit works nicely, too. You must use a cast iron skillet!! If you don't have one, go buy one and season it well...it's a kitchen necessity!