Lightly oil a 13-inch springform pan with coconut oil.
In the bowl of a food processor, place the walnuts and pulse until mealy.
Drain water from dates. Remove and discard the pits from the dates (you can compost them).
With the motor running, add the dates to the bowl of the food processor one at a time and blend until the dough balls up on the side of the bowl.
Press the dough into the bottom of the prepared springform pan until even. Sprinkle with salt and cayenne.
Drain and rinse cashews. In the pitcher of a Vitamix, place the cashews, coconut milk, agave, cacao powder, and cinnamon. Blend on medium speed for 30 seconds, then increase to high speed and blend for 1 minute more or until the filling is smooth.
Pour the filling into the crust and smooth out with a rubber spatula.
Place the pie in the freezer to set for at least 8 hours or overnight.
Remove the pie from the freezer. Let stand 30 minutes before serving. Garnish with cacao nibs and dust with cinnamon.