Preheat the oven to 350°F (175°C) and line a baking sheet with parchment. In a large bowl, whisk together the melted butter, pumpkin puree, sweetener, egg, and vanilla until smooth.

In a separate bowl, whisk together the almond flour, baking powder, pumpkin pie spice, and salt.

Stir the dry ingredients into the wet mixture with a spatula until no dry streaks remain. The dough will be soft and slightly sticky.

Drop rounded tablespoons of dough onto the sheet, spacing them 2 inches apart. Lightly flatten each mound to about ½ inch thick. Bake for 12 to 15 minutes, until the edges are set and just golden.

Let the cookies rest on the baking sheet for 5 minutes, then transfer to a wire rack to cool completely before serving.