Grandma's Texas Chocolate Sheet Cake

Square close up of a slice of Texas sheet cake on a white plate.

5 from 2 votes

Grandma's Texas Chocolate Sheet Cake

This old-fashioned Texas sheet cake is a rich, moist chocolate cake topped with a warm fudge frosting that sets like ganache. It bakes in one pan and feeds a crowd, so it's perfect for potlucks, birthdays, and summer cookouts!

Course Dessert

Cuisine American

Keyword old fashioned texas sheet cake, texas chocolate sheet cake, Texas Sheet Cake, texas sheet cake recipe

Prep Time 20

Cook Time 20

Cooling Time 3

Total Time 3 40

Servings people

Calories 329kcal

Author Blair Lonergan

Equipment

10 x 15 inch jelly roll pan

Ingredients

FOR THE CAKE

½ cup (1 stick) salted butter
½ cup shortening
1 cup water
¼ cup unsweetened cocoa powder
2 cups granulated sugar
2 cups all-purpose flour
1 teaspoon baking soda
1 teaspoon salt
2 large eggs
½ cup buttermilk
1 teaspoon vanilla extract

FOR THE FROSTING

½ cup (1 stick) salted butter
¼ cup unsweetened cocoa powder
6 tablespoons whole or 2% milk
16 oz confectioners’ sugar, sifted
1 teaspoon vanilla extract
1 cup chopped pecans (optional)
Optional garnish: rainbow sprinkles

Instructions

FOR THE CAKE

Preheat the oven to 400°F. Grease a 10 x 15-inch jelly roll pan and set it aside.
In a saucepan, combine the butter, shortening, water, and cocoa powder. Bring to a boil over medium heat, whisking just until the butter and shortening melt, then remove from the heat.
In a large bowl, whisk together the sugar, flour, baking soda, and salt.
Pour the hot cocoa mixture over the dry ingredients and beat with an electric mixer on medium speed for 1 minute.
Add the eggs, buttermilk, and vanilla. Beat on medium speed for 1 minute more. The batter will be thin and pourable, which is exactly what you want.
Pour the batter into the prepared pan and tap it on the counter a few times to release air bubbles.
Bake for 20 to 23 minutes, until a toothpick inserted in the center comes out clean.
Set the pan on a wire rack. If the cake domed at all, gently press the top flat with a clean towel while it's warm so the frosting won't run off the sides. Leave the cake in the pan and make the frosting right away.

FOR THE FROSTING

In a saucepan, combine the butter, cocoa powder, and milk. Bring to a boil, whisking just until the butter melts, then remove from the heat.
Beat in the sifted confectioners' sugar and vanilla until smooth and glossy. Fold in the pecans, if using.
Pour the warm frosting over the warm cake and spread it to the edges with an offset spatula. Add sprinkles now, if using. Set the cake on a wire rack and cool completely; the frosting firms up like a fudgy ganache as it sits.
Slice into squares and serve.

Notes

Don't skip the buttermilk. Regular milk won't work here. The acid in buttermilk keeps the cake moist and reacts with the baking soda to help it rise.
Shortening swap. No shortening on hand? Use all butter. The cake will be a little denser but still delicious.
Sift the sugar. Sifting the confectioners' sugar before it goes into the frosting is the easiest way to keep it smooth and lump-free.
9x13 pan option. You can bake this in a 9x13-inch pan instead. The cake will be thicker, so lower the oven to 350°F and add about 15 minutes to the bake time. Test the center with a toothpick.
Make it festive. Add ¾ cup toasted chopped pecans to the hot frosting, or scatter on colored sprinkles. Tailor the colors to the occasion, like orange and black for Halloween or red and green for Christmas.
Make ahead. Bake it a day in advance (it tastes even better the next day), or freeze the frosted cake for up to 3 months.

Nutrition