Ingredients:

  • 250g all-purpose flour
  • 400g granulated sugar
  • 2g salt
  • 5g baking soda
  • 227g unsalted butter
  • 30g unsweetened cocoa powder
  • 240ml boiling water
  • 120ml buttermilk
  • 2 large eggs, room temperature
  • 5ml vanilla extract
  • 113g unsalted butter (for glaze)
  • 30g unsweetened cocoa powder (for glaze)
  • 90ml whole milk
  • 450g powdered sugar, sifted
  • 5ml vanilla extract (for glaze)
  • 100g finely chopped pecans

Instructions:

  1. Preheat your oven to 350°F (175°C) and grease an 18x13 inch jelly roll pan.
  2. In a large mixing bowl, whisk together the flour, granulated sugar, salt, and baking soda.
  3. In a medium saucepan over medium heat, combine 227g butter, 30g cocoa powder, and water. Bring the mixture to a rolling boil for 30 seconds, then immediately pour it over the dry ingredients. Whisk until no flour streaks remain.
  4. Add the buttermilk, eggs, and vanilla to the warm chocolate mixture. Whisk vigorously until the batter is smooth and glossy. Pour into the prepared pan.
  5. Bake for 18-20 minutes or until a toothpick inserted into the center comes out clean.
  6. While the cake is baking, prepare the glaze by combining 113g butter, 30g cocoa powder, and milk in a saucepan. Bring to a boil, then remove from heat and whisk in the powdered sugar, vanilla, and pecans.
  7. Pour the warm glaze over the cake immediately after removing it from the oven, spreading it to the edges. Let the cake cool completely before slicing into 24 squares.