Use a pastry brush to coat wells of a doughnut maker (or the wells of a doughnut pan.
In a large bowl whisk together low carb baking mix, almond flour, cocoa powder, granulated sugar substitute, baking powder, baking soda, salt and xanthan gum. Stir in eggs, melted butter, and vanilla until thoroughly combined. Add almond milk and stir until smooth.
Fill wells of doughnut maker, or fill wells of doughnut pan 2/3rds full. Bake according to doughnut maker's instructions, or 18 to 20 minutes if using a doughnut pan, or until set and donuts spring back when touched. Flip out onto a wire rack to cool completely. Repeat with remaining batter.
Once doughnuts have cooled, spread with peanut butter frosting and sprinkle with chocolate covered pretzel pieces.
Makes 12 mini donuts or about 6 regular sized doughnuts