Ingredients:

  • 1 cup (225g) unsalted butter, softened
  • 1 cup (200g) granulated sugar
  • 1 cup (215g) packed light brown sugar
  • 2 large eggs, room temperature
  • 1 tsp pure vanilla extract
  • 1.5 cups (375g) creamy peanut butter, divided
  • 2 cups (250g) all-purpose flour
  • 1 cup (100g) fine graham cracker crumbs
  • 1 tsp baking soda
  • 0.5 tsp salt
  • 0.5 cup (115g) unsalted butter (for frosting)
  • 0.25 cup (25g) unsweetened natural cocoa powder
  • 0.33 cup (80ml) whole milk
  • 3.5 cups (420g) powdered sugar, sifted
  • 1 tsp vanilla extract (for frosting)

Instructions:

  1. Preheat your oven to 350°F (175°C) and line a 9x13 inch baking pan with parchment paper, leaving an overhang on the sides for easy removal.
  2. In a large bowl or stand mixer, cream together 1 cup of softened butter, granulated sugar, and brown sugar until light and fluffy (about 3 minutes).
  3. Beat in the eggs one at a time, followed by 1 teaspoon of vanilla extract and 1 cup of creamy peanut butter until fully combined.
  4. Whisk together the flour, graham cracker crumbs, baking soda, and salt. Gradually add the dry ingredients to the wet ingredients, mixing just until combined.
  5. Spread the dough evenly into the prepared 9x13 pan. Bake for 20 minutes, or until the edges are lightly golden and the center is set.
  6. Immediately after removing from the oven, dollop the remaining 1/2 cup of peanut butter over the warm bars. Let it sit for a minute to melt, then spread it into a thin, even layer using an offset spatula.
  7. Prepare the frosting by combining 1/2 cup butter, cocoa powder, and milk in a medium saucepan. Bring to a boil over medium heat, stirring constantly.
  8. Remove the chocolate mixture from heat and whisk in the powdered sugar and 1 teaspoon of vanilla until smooth. Pour the warm frosting over the peanut butter layer and spread quickly.
  9. Allow the bars to cool completely at room temperature until the frosting is set and develops a thin, shattering crust before slicing into 24 bars.