Granny’s Sheet Cake is a classic chocolate sheet cake that has been a family favorite for generations. Made with simple pantry ingredients and topped with a warm chocolate nut frosting, this moist and flavorful cake is perfect for potlucks, birthdays, holidays, and family gatherings. Best of all, it makes enough to feed a crowd.
Ingredients
For the Cake
- 1 cup granulated sugar
- 1 cup brown sugar
- 2 cups all-purpose flour, measured then sifted
- 1 teaspoon salt
- 1 cup butter
- 2/3 cup water
- 1/2 cup cocoa powder, heaping
- 1 cup sour cream or buttermilk
- Or 1/2 cup milk mixed with 2 tablespoons vinegar
- 2 large eggs
- 1 teaspoon baking soda
- 2 teaspoons vanilla extract
For the Butter Nut Frosting
- 1/2 cup butter or margarine
- 2 cups powdered sugar, heaping, measured then sifted
- 4 tablespoons whole milk, cream, or canned milk
- 3 tablespoons cocoa powder, heaping
- 1 teaspoon vanilla extract
- 1 cup chopped pecans, walnuts, or almonds (optional)
Instructions
Prepare the Cake
- Preheat the oven to 375°F (190°C).
- Grease and flour a 17 x 12-inch sheet pan.
- In a large bowl, sift together the granulated sugar, brown sugar, flour, and salt. Set aside.
- In a heavy saucepan over medium-low heat, combine the butter, water, and cocoa powder.
- Stir constantly until the butter melts and the mixture is smooth.
- Remove from heat and immediately pour into the flour mixture. Stir until well combined.
- In a separate bowl, whisk together the eggs, sour cream or buttermilk, vanilla extract, and baking soda.
- Add the wet mixture to the batter and mix until smooth.
- Pour the batter into the prepared sheet pan and spread evenly.
- Bake for 20 to 25 minutes or until a toothpick inserted into the center comes out clean.
Make the Butter Nut Frosting
- While the cake is baking, melt the butter and cocoa powder together in a saucepan.
- Add the milk and cook for 1 minute, stirring constantly.
- Remove from heat and whisk in the powdered sugar and vanilla until smooth.
- Stir in the chopped nuts if using.
Frost the Cake
- Allow the cake to cool for about 5 minutes after removing it from the oven.
- Pour the warm frosting over the warm cake.
- Spread evenly to the edges using a spatula.
- Let the cake cool completely before slicing.
Notes
- Pecans are the traditional choice, but walnuts or almonds work well too.
- Frosting the cake while both the cake and frosting are warm helps create the signature smooth finish.
- Store covered at room temperature for up to 3 days.
- This cake freezes well for up to 3 months.
