Start with your pie crust. Add the flour, butter, salt, and sugar to a food processor. Pulse about 6 times, or until the mixture resembles large crumbs the size of lentils.
Add in the egg and pulse until just combined. Add in the water one tablespoon at a time as needed. The mixture should resemble gritty sand, but hold together when pressed.
Turn out the mixture onto a flat surface and press together. Form into a disc and wrap tightly in plastic wrap. Place in the refrigerator for at least an hour.
While the pie is chilling, make the fillings.
Start the chocolate pumpkin layer. Mix together the ingredients, except the chocolate. Mix until well combined.
Add the chocolate to a small microwave-safe bowl and heat on 50% power for 30 seconds. Mix well. If the chocolate isn't fully melted, heat for another 30 seconds. Repeat until the chocolate is fully melted.
Take one cup of the pumpkin filling and add it to the chocolate. Mix until well-combined. Set aside.
Make the Pecan layer. Mix together all the ingredients, except for the pecans. Make sure the mixture is well-combined, but not over-mixed. Fold in the chopped pecans.
Preheat the oven to 350 degrees F, Roll out the dough once it's chilled for an hour. . Place the dough on a lightly floured surface and roll into a large circle about ¼ inches thick and wide enough to extend far beyond the diameter of your pie dish. Place the crust in the pie dish and trim the edges of the crust so it is only about an inch over the pie dish all around. Tuck under the excess left on the crust and crimp. Roll out any leftover crust and shape into leaves if desired.
Assemble. Alternate adding the chocolate pumpkin and the regular pumpkin into the pie dish. Lightly swirl. Top with the pecan pie layer. Top with the leaves, if using, then decoratively add the pecan halves.
Brush the edges of the pie crust and the leaves with the egg wash.
Bake for 55 - 60 minutes, or until the edges of the pie is set and the middle is only slightly jiggly. Please be careful as this as it is easy for the pecan layer to become underbaked. If the middle still feels too jiggly, but the pecans are getting too dark, cover in aluminum foil and continue baking, checking ever 5 minutes.
Allow to cool completely before cutting and serving.
Notes
*You can also use light/regular if you can't find darkIf you use the FoodSaver to save slices of pie, I recommend chilling the pie first for best results.