In a food processor, combine both of the flours, sugar and salt. Pulse until mixed. Chop up the chilled coconut oil and add it to the processor. Pulse until it becomes crumbly (the size of peas). Next, add the water and process until it's completely combined.

Remove dough from the food processor and form the it into a ball and wrap in plastic wrap. Refrigerate for 30 minutes to an hour.

Massage the ball of dough with your hands until it becomes soft and manageable. Then, place the ball of dough into a lightly greased pie pan. Press the dough down and create an even bottom layer and press the dough up the sides of the pan. I usually take my time with this to get it perfectly even. I find this process to be much easier and faster than rolling the dough out and then transfer the dough to the pan. 

Cover and pie crust and set in the freezer for 1 hour.

In the meantime, make prepare the walnut and veggie mixture. Preheat your oven to 400 degrees F. In a large bowl, add all of the mushrooms, walnuts, veggies and seasonings and mix to combine, making sure all of the nuts and veggies are evenly coated. Pour mixture onto a cast iron skillet or a parchment paper lined baking sheet. Bake until veggies and nuts are tender, about 30 minutes. 

While nuts and veggies are baking, make the black bean sauce by combining all of the ingredients in a food processor and processing until smooth. Transfer to a large mixing bowl and set aside until ready for use. 

After nuts and veggies are done roasting, reduce your oven temperature to 350 degrees F. Transfer them to the bowl of black bean sauce. Mix to combine. 

Remove crust from freezer and pour bean mixture onto the crust, forming an even layer. 

Bake for 40-45 minutes, or until crust is golden brown.

Remove from oven, top pie with a layer of vegan sour cream, tortilla chips, lettuce, pico de gallo and olives.

Slice, serve and enjoy! Store leftovers covered in the refrigerator for up to a week.