• Preheat oven 350 degrees. 
• In a large bowl, using a hand or stand mixer, mix the butter, cookie butter, and both sugars until light and creamy. Beat in the egg. Set aside.
• In a small bowl, whisk the flour, baking soda, and salt. Add the flour mixture into the wet mixture and combine with a spatula or spoon. 
• Using a medium cookie scoop, or a heaping tablespoon, scoop the dough and place 2 inches apart onto an ungreased cookie sheet. 
• Bake for 12-14 minutes, until the edges are set. Cool for 2-3 minutes on the sheet and move to a cooling rack to finish. Allow to completely cool before filling the cookies.

For the Filling

• In a medium bowl, using a hand or stand mixer, cream the butter and cookie butter until combined. Add in the vanilla and mix. Add in the powdered sugar and continue mixing until well combined. 
• Add 1-2 tbsp of filling to the bottom of a cookie, spread, and then top with another cookie.