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G.G.'s Chocolate Sheet Cake

This is my great-grandmother's recipe that she passed down to me, and it is quite simply the best chocolate dessert I have ever had. It's so simple and so yummy! Beware--if you bring this to a party it will go fast!
Print Recipe
Prep Time 30 minutes
Cook Time 20 minutes
Total Time 1 hour 50 minutes
Course lunch/dinner, Snack
Cuisine American
Servings 48 people
Calories 7720.7 kcal

Equipment

  • 1 Jelly Roll Pan 11x17 inch recommended
  • 1 Large Mixing Bowl
  • 2 Small Saucepan One for cake base, one for frosting
  • 1 Whisk or Electric Mixer For mixing batter and frosting
  • 1 Wire Rack For cooling the cake

Ingredients
  

Main

  • 2 cups white sugar
  • 2 cups all-purpose flour
  • 1 cup butter melted
  • 1 cup water
  • 3 tablespoons unsweetened cocoa powder
  • 1 teaspoon baking soda
  • ½ cup buttermilk
  • 2 eggs
  • 1 teaspoon vanilla extract
  • ½ cup butter
  • 3 tablespoons unsweetened cocoa powder
  • 5 tablespoons milk
  • 1 16 ounce box confectioners' sugar
  • 1 cup chopped pecans

Instructions
 

  • Preheat an oven to 350 degrees F (175 degrees C). Grease an 11x17 jelly roll pan.
  • Mix white sugar and flour in a large bowl. Combine 1 cup butter, water, and 3 tablespoons cocoa powder in a small saucepan; stir over medium heat until butter is melted and mixture is well combined. Pour melted butter mixture over sugar and flour; beat well. Beat in baking soda, buttermilk, eggs, and vanilla extract. Pour batter into prepared pan.
  • Bake in preheated oven until a toothpick inserted into the center of cake comes out clean, 20 to 25 minutes. Remove from oven and allow to cool on a wire rack.
  • Combine remaining 1/2 cup butter, 3 tablespoons cocoa powder, and milk in a small saucepan; stir over medium heat until butter is melted and mixture is well combined. Beat powdered sugar into the butter mixture, mixing until frosting is smooth. Stir pecans into frosting and pour over cooled cake.

Notes

For an intensified chocolate flavor, consider using Dutch-processed cocoa powder in both the cake and frosting. A small amount of espresso powder (about 1/2 teaspoon) can also deepen the chocolate notes without imparting a coffee taste. When mixing the wet and dry ingredients for the cake, be mindful not to overmix, as this can develop gluten and lead to a tougher cake texture. For the frosting, toasting the pecans lightly before stirring them in will enhance their nutty aroma and flavor. Ensure the cake is fully cooled before applying the frosting to prevent it from melting and becoming runny. For a richer, thicker frosting, consider creaming softened butter instead of melting it, then gradually incorporating the powdered sugar and cocoa.