1. Combine first 9 ingredients in a large mixing bowl. Spoon mixture into an 8 1/2- x 11-inch baking dish.
2. Stir together dark brown sugar and next 3 ingredients in a medium bowl. Cut in butter with a pastry blender or fork until mixture forms pea-size pieces. Spoon topping evenly over filling, and bake at 375° for 50 minutes or until fruit is bubbling and top is golden. Spoon Crisp Topping evenly over the crumble, if desired. Serve warm. (Crumble may be made ahead and reheated in a 350° oven 10 minutes).