Preheat oven to 175°C (350°F). Line a 9x9-inch baking pan with parchment.
In a bowl, mix almond flour, sweetener, butter, vanilla, and salt. Press into pan to form crust.
Bake crust for 10–12 minutes until lightly golden.
Meanwhile, melt butter in a saucepan, then whisk in brown sweetener until dissolved.
Remove from heat, whisk in eggs one at a time, then add vanilla and salt.
Stir in pecans until coated.
Pour filling over crust, spreading evenly.
Bake 25–30 minutes until filling is set.
Cool completely before slicing into bars.