Ingredients:

  • 2 ½ cups All-Purpose Flour (315 g)
  • 1 teaspoon Baking Soda (5 g)
  • ½ teaspoon Fine Sea Salt (3 g)
  • 1 cup (2 sticks) Unsalted Butter, softened (226 g)
  • 1 cup Creamy Peanut Butter (250 g)
  • 1 cup Light Brown Sugar, packed (220 g)
  • ½ cup Granulated Sugar (100 g)
  • 2 Large Eggs
  • 1 teaspoon Pure Vanilla Extract
  • 1 ½ cups Powdered Sugar (Confectioner's), sifted (180 g)
  • ¼ cup Unsweetened Cocoa Powder (25 g)
  • ¼ cup (4 Tablespoons) Unsalted Butter, melted (56 g)
  • 3 – 4 Tablespoons Milk (Whole or 2%)
  • ½ teaspoon Pure Vanilla Extract (for glaze)

Instructions:

  1. Preheat the oven to 350°F (175°C). Line the 9x13 inch pan with parchment paper, leaving an overhang on the long sides (this acts as a sling later). Lightly grease the parchment.
  2. In a medium bowl, whisk together the flour, baking soda, and salt. Set aside.
  3. In the bowl of a stand mixer, cream the softened butter, creamy peanut butter, brown sugar, and granulated sugar on medium speed until the mixture is light and fluffy—about 3 minutes.
  4. Reduce speed to low. Beat in the eggs one at a time, mixing well after each addition. Scrape down the bowl, then mix in the vanilla extract.
  5. Add the dry flour mixture to the wet mixture. Mix only on low speed until just combined. Stop immediately when no streaks of flour remain. Do not overmix!
  6. Press the cookie dough evenly and firmly into the prepared 9x13 pan. Use a clean, damp hand or the bottom of a measuring cup to ensure the dough is compacted and level.
  7. Bake for 25–30 minutes, or until the edges are golden brown and the centre is set (it should look slightly matte, not shiny).
  8. Transfer the pan to a wire rack. Let the bars cool fully before applying the glaze (about 45–60 minutes).
  9. Prepare Glaze: In a medium bowl, sift the powdered sugar and cocoa powder together to prevent lumps.
  10. Make the Glaze: Pour the melted butter and vanilla into the powdered mixture. Add 3 tablespoons of milk and whisk vigorously until smooth. Add the remaining milk, one teaspoon at a time, until the glaze is thick enough to pour but not runny.
  11. Glaze the Bars: Once the bars are completely cool, pour the chocolate glaze over the top. Use an offset spatula to spread it evenly to the edges.
  12. Set and Slice: Allow the glaze to set completely (15–30 minutes at room temperature). Use the parchment sling to lift the entire block out of the pan. Slice into 24 squares using a large, sharp knife.