Preheat the oven to 350˚F. Lightly grease an 11- x -7-inch baking dish. Stir together the cornstarch and ½ cup of the sugar. Toss the berries with the cornstarch mixture, and spoon into the prepared baking dish.

Beat the butter at medium speed with an electric mixer until fluffy; gradually add the remaining 1 cup sugar, beating well. Add the eggs, 1 at a time, beating just until blended after each addition.

Combine the flour and baking powder. Stir together the sour cream and baking soda. Add the flour mixture to the butter mixture alternately with the sour cream mixture, beginning and ending with flour mixture. Beat at low speed just until blended after each addition. Spoon the batter over the berry mixture.

Bake at 350˚F for 45 minutes; shield loosely with aluminum foil to prevent excessive browning, and bake at 350˚F for 20 to 25 more minutes or until a wooden pick inserted in center of the cake topping comes out clean.

Layer the cobbler in parfait glasses with the vanilla ice cream, caramel sauce, and the slated pecans.