Apple Pie with Oat Streusel

For crust:

Position rack in center of oven; preheat to 400°F. Place rimmed baking sheet in bottom of oven to catch spills. Place sheet of parchment paper on work surface; lightly flour parchment. Place dough disk on parchment; sprinkle very lightly with flour. Cover with another sheet of parchment; roll to 9-inch round. Remove top parchment; sprinkle oats evenly over crust. Cover again with top parchment; roll to 12-inch round, rolling oats into crust. Remove top parchment. Using bottom parchment as aid, invert crust, oat side down, into 9-inchdiameter glass pie dish. Remove parchment. Press crust gently into pie dish. Turn dough overhang under, forming high-standing rim 1/2 inch above sides of dish. Crimp edges.

For filling:

Toss all ingredients in large bowl. Let stand while preparing topping.

For topping:

Blend first 6 ingredients in processor. Add butter; using on/off turns, blend until moist dough forms (mixture will resemble wet sand). Add oats; using on/off turns, mix briefly, leaving half of oats whole. Stir filling; transfer to crust, mounding in center. Sprinkle topping evenly over.

Bake pie until topping is golden, about 40 minutes. Reduce oven temperature to 350°F. Bake until apples are tender when pierced with small sharp knife, covering pie loosely with foil if topping and crust are browning too quickly, about 1 hour longer. Cool pie on rack until slightly warm, at least 1 hour. Serve warm or at room temperature.