1. For crust, soak 1 cup pecans in 2 cups fresh water for 2-4 hours. Drain and rinse. In a food processor, chop 1 cup dry pecans into a fine meal. Set aside. Chop soaked pecans into a fine meal.
2. Cut or break the dates into pieces. If the dates are very dry or firm, soak them in 1/2 cup fresh water for 5 minutes to soften. Add the date pieces, vegan maple syrup, cocoa, cinnamon, nutmeg, vanilla, and sea salt to the ground soaked pecans and chop until well mixed.
3. Add the ground dry pecans and chop until well mixed. The dough should be crumbly but sticky enough to hold shape when pressed. Press the dough evenly into a pie plate; it is easiest to press the dough first to the sides of the plate and then press into the bottom for an even depth.
4. For filling, in a blender, cream together avocados, lemon juice, and vanilla. In a double broiler, melt chocolate chips; let chocolate cool slightly.
5. Add melted chocolate to the avocado mixture and blend until smooth. Pour into prepared crust and chill overnight.