Preheat the oven to 350 degrees. Line a few baking sheets with parchment and set aside.

In the bowl of a stand mixer, combine the peanut butter, butter and sugars.  Cream until smooth.

Add in the vanilla and egg.  Mix well.

Add in the flour, baking powder, baking soda, corn starch and salt.  Mix thoroughly, scraping down the sides often.

Using a large ice cream scoop, divide the cookie dough between the prepared baking sheets.  Gently flatten into a disc.

Bake in the preheated oven for approximately 10 minutes or until the centers are set.  Allow to cool completely before decorating.

For the frosting - in the bowl of a stand mixer, combine the butter, peanut butter and powdered sugar.  Cream until smooth, scraping down the sides as needed.  Transfer the frosting to a piping bag and set aside.

Fill another piping bag with the raspberry jam and set aside.

To assemble - once the cookies are cool, pipe a large swirl of peanut butter frosting around the top of each cookie.

Fill in the void of the swirl with the raspberry jam.