Beat the butter and powdered erythritol with an electric mixer on medium speed until pale and fluffy, about 2 minutes.

Add the almond flour, vanilla, and salt, and mix on low just until a dough forms, 30 to 45 seconds.

Roll the dough between two sheets of parchment to 1/4-inch thickness, cut out cookies, and chill the rounds on a parchment-lined tray for 10 minutes.

Preheat the oven to 350°F (175°C), then bake the chilled rounds on a parchment-lined sheet for 11 to 13 minutes until the edges are golden.

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