In a large mixing bowl, beat the softened butter until smooth and creamy.
Add the brown sugar and continue mixing until well combined.
Add the egg yolks and vanilla extract.
Beat until the mixture is light and fluffy.
Add the creamy peanut butter.
Mix until the peanut butter is fully incorporated and the mixture is smooth.
Gradually add the prepared dry ingredients (all-purpose flour, baking powder, baking soda, and salt).
Mix gently with a spatula until all the ingredients are fully incorporated and a smooth, soft cookie dough forms with no dry flour remaining. Do not overmix.
In a medium saucepan, combine the chopped strawberries, granulated sugar, and vanilla extract.
Cook over medium heat until the strawberries soften and the mixture thickens into a jam. Remove from the heat and let it cool completely.
Scoop equal portions of the dough, roll them into smooth balls, and arrange them on a parchment-lined baking sheet, leaving about 2 inches of space between each cookie.
Gently press the center of each dough ball with the back of a measuring spoon or your thumb to create a shallow indentation.
Bake in a preheated 350°F (175°C) oven for 10–12 minutes, or until the edges are lightly golden and the centers are set. Let the cookies cool completely before filling with the peanut butter frosting and strawberry jam.
Meanwhile, prepare the peanut butter frosting by melting the peanut butter with the heavy cream until smooth. Let the mixture cool, then whip until light, fluffy, and pipeable.
Pipe the peanut butter frosting into the center of each cooled cookie, then spoon the cooled strawberry jam over or into the center of the frosting.
Finish with a drizzle of melted peanut butter and garnish with fresh strawberry slices, if desired.
Serve immediately or store in an airtight container.
