1. Preheat oven to 375°.
2. To prepare pie, weigh or lightly spoon flour into dry measuring cups; level with a knife. Combine 1 1/2 ounces (about 1/3 cup) flour, granulated sugar, cinnamon, and salt in a large bowl. Add juice and pears to flour mixture; toss gently to coat. Roll dough into an 11-inch circle; fit dough into a 9-inch pie plate coated with cooking spray. Fold edges under and flute. Arrange pear mixture in an even layer in prepared crust.
3. Combine remaining 1 1/2 ounces (about 1/3 cup) flour and 1/3 cup brown sugar in a bowl. Add 3 tablespoons cold butter to brown sugar mixture; cut in with a pastry blender or 2 knives until mixture resembles coarse meal. Sprinkle butter mixture evenly over pears. Bake at 375° for 1 hour or until lightly browned. Let cool on a wire rack 10 minutes.
4. To prepare sauce, combine 1/3 cup brown sugar, cream, and 2 tablespoons softened butter in a small, heavy saucepan over medium-high heat; bring to a boil. Cook 1 minute or until thickened. Remove from heat; stir in 2 teaspoons water. Serve at room temperature or slightly warmed with pie.