1. Preheat oven to 350°.
2. Place pears in a large bowl. Sprinkle with 6 tablespoons brown sugar, 2 tablespoons flour, juice, and salt; toss well to coat. Transfer mixture to an 11 x 7–inch baking dish coated with cooking spray.
3. Place cookies in a food processor; process until finely ground. Weigh or lightly spoon remaining 2.25 ounces (about 1/2 cup) flour into a dry measuring cup. Combine 2.25 ounces flour, cookie crumbs, and remaining 2 tablespoons brown sugar in a medium bowl; cut in butter with a pastry blender or 2 knives until mixture resembles coarse meal. Stir in nuts. Sprinkle crumb mixture evenly over pear mixture. Bake at 350° for 50 minutes or until pears are tender. Let stand 10 minutes.
4. Combine cream and powdered sugar in a medium bowl. Beat with a mixer at high speed until stiff peaks form. Divide crisp evenly among 9 bowls; top each serving with about 1 tablespoon whipped cream.