To make the pie crust, combine flour and sugar in a food processor. Add butter and pulse until crumbly. With processor running, add water one tablespoon at a time until dough comes together and forms a ball. Turn out onto a sheet of plastic wrap and shape into a disc. Chill for 30 minutes. On a lightly floured surface, turn out dough and roll into a 12-inch circle. Lift dough using a rolling pin (if dough is hard to work with, return to the refrigerator to help it firm up a bit) and lay over a lightly greased 9-inch pie plate. Gently press into pie plate and flute the edges. Beat egg and milk with a fork until pale and frothy. Brush egg wash over edges of pie crust.
For the pie filling, preheat oven to 350°F. Beat butter and sugar on medium-high speed with an electric mixer until fluffy. Add maple syrup, eggs, vanilla, and bourbon. Mix well. Add flour and salt; mix until well blended. Fold in chocolate chips and pecans. Pour pie filling into the prepared crust and arrange pecans halves over the top. Bake 45-50 minutes (tent with foil if crust begins to brown too quickly), or until pie is set around the edges and slightly jiggly in the center. Let pie cool 1-2 hours before serving.
To make the whipped cream, combine all ingredients and mix on high speed with an electric mixer until stiff peaks form. Serve with pie.