Preheat oven to 350°F (175°C).
For the crust, combine almond flour, melted butter, and egg until a dough forms. Press into a 9-inch pie pan.
In a saucepan over medium heat, melt brown sugar substitute and butter together, stirring until smooth, about 4–5 minutes.
Remove from heat and whisk in cream, then eggs one at a time, then vanilla and salt.
Stir in toasted pecans and pour filling into the crust.
Bake 40–45 minutes, until the center is set with a slight jiggle.
Cool completely before slicing.