Preheat your oven to 350°F (175°C).
In a bowl, mix almond flour, coconut flour, and powdered erythritol for the crust.
Add melted butter and vanilla extract to form a dough. Press it into a pie pan.
Bake the crust for 10 minutes and set aside.
In another bowl, whisk eggs, sugar-free maple syrup, and a pinch of salt.
Fold in pecan halves and pour the filling into the crust.
Bake for 40-45 minutes until the filling is set.
Let cool before serving.