Preheat oven to 375°. On a lightly floured surface, roll dough to a 1/8-in.-thick circle; transfer to a 9-in. pie plate. Trim crust to 1/2 in. beyond rim of plate; flute edge. Refrigerate while preparing filling.
In a large bowl, combine peaches, sugar, flour and nutmeg. In a small bowl, whisk egg and cream. Pour over peaches; toss to combine. Place in crust. Bake 35 minutes.
For topping, in a small bowl, combine flour, brown sugar and cinnamon. Cut in butter until crumbly. Sprinkle topping over outer edges of pie, leaving center uncovered.
Bake 15-20 minutes or until golden brown, covering edges with foil to prevent overbrowning if necessary. Cool on a wire rack. Serve with whipped cream if desired.
Combine 1-1/4 cups all-purpose flour and 1/4 tsp. salt; cut in 1/2 cup cold butter until crumbly. Gradually add 3-5 Tbsp. ice water, tossing with a fork until dough holds together when pressed. Shape into a disk; wrap and refrigerate 1 hour.