Don't let the name scare you off -- this slump is very similar to your usual cobbler. Filled blackberries and blueberries and covered with an easy biscuit topping, this fall dessert is a definite must-try.
Preheat oven to 350 degrees F. In a medium bowl stir together the first five ingredients (through salt). Stir in milk, melted butter, and vanilla just until combined.
In a small saucepan cook and stir water and the 1/2 cup sugar over medium-high heat until sugar is dissolved. Remove from heat. In a 2-qt. baking dish combine blackberries, blueberries, and, if desired, lemon zest. Spread batter evenly over fruit (may not completely cover fruit). Drizzle sugar-water over batter.
Bake 50 to 60 or until a toothpick inserted in cake comes out clean and cake is golden. Cool slightly; serve warm. If desired, top with whipped cream.