1. Preheat the oven to 350°F (175°C) and grease a 12-cup muffin pan.

2. Mix the almond flour, powdered sugar-free sweetener, salt, melted butter, and vanilla until a soft dough forms.

3. Divide the dough evenly among the muffin cups and press into the bottoms and up the sides to form mini pie crusts.

4. Bake the crusts for 8 to 10 minutes until lightly golden, then allow them to cool slightly.

5. In a saucepan, melt the butter with the brown sugar-free sweetener and heavy cream until smooth.

6. Remove from the heat and whisk in the egg, vanilla extract, salt, and xanthan gum if using.

7. Fold in the pecan halves until evenly coated.

8. Spoon the filling into each baked crust and top with extra pecan halves if desired.

9. Bake for 18 to 22 minutes until the filling is mostly set with a slight jiggle in the center.

10. Cool completely before removing from the muffin pan and serve at room temperature or chilled.