Pear-Aronia Berry Pie with Oatmeal Streusel

For the streusel:
3/4 cup regular oats
1/2 cup packed light brown sugar
1/2 teaspoon ground cinnamon
1/4 teaspoon ground nutmeg
Dash of salt
2 Tablespoons chilled butter, cut into small pieces

For the filling:
3 cups (1/2-inch) cubed peeled Anjou pear (3 large)
2 cups fresh aronia berries or frozen (thawed)
2/3 cup light brown sugar
2-1/2 Tablespoons cornstarch

Remaining ingredient:
1 unbaked 9-inch deep-dish pastry shell

Preheat oven to 350 degrees. Prepare streusel by combining first five ingredients in a medium bowl; cut in butter with a pastry blender or 2 knives until mixture resembles a coarse meal.
Combine pear, aronia berries, 2/3 cup brown sugar and cornstarch in a large bowl; toss well to combine.  Spoon pear mixture into pastry shell; sprinkle streusel over pear mixture.  Bake at 350 degrees for 1 hour or until bubbly and streusel is browned.  Cool at least 1 hour on a wire rack. Serve with vanilla ice-cream or a sweetened whipped cream.