Begin by preheating your oven to 350 degrees F In a bowl whisk together 1 Cup all purpose flour 1/2 tsp baking powder 1/2 tsp baking soda 1/2 tsp salt 1 tsp cornstarch

In a stand mixer or with a hand held mixer cream together 1/2 Cup creamy peanut butter 1/2 Cup unsalted softened butter

Add to the mixer 1/2 Cup brown sugar 1/2 Cup granulated sugar 1 tsp vanilla 1 egg warmed to room temperature Mix until everything is fully combined, then gradually add in the flour mixture

Once a soft dough ball is formed, remove from the mixer, cover in wrap and chill in the fridge for 30 minutes

Line a baking sheet with parchment paper or a silpat mat and place cookie dough balls onto the sheet

Flatten the center of each unbaked cookie with the back of your finger

Add a small amount of marshmallow cream into the well of each cookie You will need roughly 3/4 Cup marshmallow cream for the entire recipe

Gently pull up the edges of the dough to enclose the marshmallow cream Bake for 10-12 minutes or until lightly golden brown Allow them to cool slightly before transferring to a cooling rack