Beat together the butter and brown sugar substitute until smooth and creamy.
Add in the remaining ingredients for the cookie batter, and blend until well combined.
Chill the dough for 3 hours.
Preheat the oven to 350 degrees.
Form the dough into 24 evenly sized balls.
Place the balls of dough onto parchment lined baking sheets, being sure to leave a bit of room between each ball of dough.
Bake for 10-12 minutes, or until cooked through completely.
Allow the cookies to cool to room temperature.
Place the confectioners sugar substitute, 1 tsp espresso powder and 1 tsp vanilla in a bowl.
Whisk in just enough almond flour to form a thick glaze.
Drizzle the icing over the cookies, and allow to set before serving.