Preheat oven to 350°. Combine flour, sugar, orange zest and salt. Cut in butter until crumbly. Add egg. Gradually add cream, tossing with a fork until a ball forms. Refrigerate, covered, until easy to handle, at least 30 minutes. , On a lightly floured surface, roll out dough into a 13-in. circle. Press onto bottom and up sides of an ungreased 11-in. fluted tart pan with removable bottom. , Combine all filling ingredients; pour into crust. For topping, whisk flour, sugar, brown sugar, salt and cinnamon. Cut in butter until crumbly. Stir in walnuts and ginger. Sprinkle over filling. , Bake until a knife inserted in center comes out clean, 45-55 minutes. Cool on a wire rack. Refrigerate leftovers.