01 -
Preheat oven to 350°F (175°C). Grease and flour an 18×13-inch rimmed baking sheet to ensure easy release after baking.
02 -
In a large bowl, thoroughly whisk together flour, granulated sugar, baking soda, and salt. Set aside.
03 -
In a medium saucepan over medium heat, melt butter with water and cocoa powder. Bring mixture to a boil, stirring frequently, then immediately remove from heat.
04 -
Pour the hot cocoa mixture over the prepared dry ingredients and stir until fully combined.
05 -
In a separate bowl, whisk together buttermilk, eggs, and vanilla extract. Add this mixture to the batter and stir until a smooth, glossy batter forms.
06 -
Pour the batter into the prepared sheet pan and spread evenly. Bake in the center rack for 20 to 25 minutes, or until a toothpick inserted in the center comes out clean.
07 -
While the cake bakes, melt butter in a saucepan over medium heat. Stir in cocoa powder and milk, bringing just to a boil. Remove from heat and gradually whisk in powdered sugar and vanilla until completely smooth.
08 -
Upon removing cake from oven, allow to cool in pan for 10 minutes. Pour fudge frosting over the warm cake, spreading evenly to the edges.
09 -
Generously drizzle caramel sauce over the frosted cake and sprinkle with chopped pecans. Allow to cool fully before slicing to serve.