Ingredients
Method
Instructions
- Preheat your oven to 350°F (175°C). Grease a 15x10x1-inch jelly roll pan or a similar sized baking sheet with sides.
- In a large mixing bowl, whisk together the flour, sugar, baking soda, and salt. Set aside.
- In a medium saucepan, combine the butter, water, and cocoa powder. Heat over medium heat, stirring occasionally, until the butter melts and the mixture comes to a gentle boil. Remove from heat.
- Pour the hot cocoa mixture over the dry ingredients and stir until just combined. The batter will be thick.
- In a small bowl, whisk together the eggs, buttermilk, and vanilla extract. Add this to the batter and mix until smooth and well combined.
- Pour the batter into the prepared pan and spread it evenly. Bake for 18-22 minutes, or until a toothpick inserted in the center comes out clean.
- While the cake is baking, prepare the icing. In a medium saucepan, combine the butter, cocoa powder, and milk. Heat over medium heat, stirring constantly, until the butter melts and the mixture comes to a boil. Remove from heat.
- Whisk in the vanilla extract, then gradually add the powdered sugar, stirring until smooth and glossy. If using nuts, stir them in at this point.
- As soon as the cake comes out of the oven, pour the warm icing over the hot cake, spreading it evenly with a spatula. The icing will set as the cake cools.
- Allow the cake to cool completely before cutting into squares and serving.
Notes
For best texture, measure flour correctly by spooning into measuring cup and leveling off. If no buttermilk, add 1 1/2 tsp lemon juice or vinegar to 1/2 cup milk and let sit 5 minutes. Pour warm icing over hot cake for signature crackly finish. Stores well at room temperature for 3 days or freezes for 3 months.
