Preheat oven at 375 degrees. Roll out the dough over an 8 inch pie plate, trimming and crimping the edge. Chill dough.
FILLING:
In a mixing bowl, beat the eggs with brown sugar.
Stir in the maple syrup, vinegar, and melted butter. Spread the coarsely chopped black walnuts evenly on the bottom of the shell.
Pour the filling over them.
Bake pie for 35 minutes.
The center will not be completely set. It will set as pie cools.
Can be made one day in advance.