• Preheat the oven to 325F and line two cookies sheets with parchment paper.
• In a medium bowl, use a fork or whisk to combine together the flour, cornstarch, baking soda and baking powder.

  Next, in a mixing bowl, beat together the butter and the two sugar alternatives until creamy. Then add the egg, vanilla and and peanut butter, mixing until smooth.
• Add the dry ingredients from the first bowl to the mixing bowl and mix until just combined.
• Scoop the dough into balls (12 total) and press the balls of dough into the cookies sheets about ½" thick.

  Bake the cookies until the edges turn gold (1bout 16-18 minutes).

  Allow the cookies to cool as directed in post.

For the topping.

• In a medium mixing bowl, cream together the butter and the peanut butter until smooth. Add the sugar free powdered sugar and vanilla along with the milk. Mix the ingredients until incorporated. You can add additional milk as needed for consistency.
• Beat the ingredients until light and fluffy (this can take a couple of minutes).

  Fill one of the piping bags with the frosting and the other piping bag with the jelly. Start by piping a swirl of the peanut butter frosting. Then fill this in with the jelly.