Heat together the milk and maple syrup. Stir 1/2 cup of this into the egg yolks and return this mixture gradually to the hot syrup mixture, beating constantly. Cook this mixture a little, then add the gelatin which has been softened in a little cold water. Add the maple flavoring and chill the mixture until it begins to thicken. Fold in the egg whites, then add the shipped cream and chopped nut meats. Pour the mixture into a baked pie shell.
This pie tastes like maple ice cream. If you double the recipe, it makes three 8-inch pies.