Preheat oven to 350 degrees F. Line a baking sheet with a Silpat or parchment paper.
Place the dry ingredients (flour, and powders) in a medium bowl. Cut the butter into the dry ingredients using a pastry cutter, or alternatively pulse them together in a food processor, until crumbly.
Add the sweetener, vanilla, and egg to the crumbly mixture and stir to combine. Form the dough into a ball.
Place the dough ball on the prepared pan and flatten it with your hands until it is about 1 inch thick. Cut it into 12 scones and separate them by a 1/2 inch. Bake for 20 minutes until lightly browned on top.
Serve immediately or allow to cool and freeze individually wrapped in waxed paper.