Add the pecans to a food processor with pitted dates, banana, and vanilla extract. Blend until you can a finely milled, sticky mixture. If the texture isn't consistent, or too dry/crumbly, add a small splash of water or plant-based milk.
Add the filling into the pie crust and spread it out evenly. Top with pecans you reserved earlier. Bake at 375F for 15-20 minutes.
You can let the pie cool down and serve it with coconut whip, or serve warm with vegan ice cream.