Chocolate Buttermilk Texas Sheet Cake

This chocolate buttermilk Texas sheet cake is baked in a 9×13-inch pan for a thicker cake with a generous layer of brown butter chocolate frosting. Dutch-process cocoa, coffee, and buttermilk give the cake its deep chocolate flavor, while the warm frosting sets into a thick, fudgy topping.

Course Cake, Dessert

Cuisine American

Keyword 9x13 Texas sheet cake, brown butter chocolate frosting, buttermilk chocolate cake, chocolate buttermilk Texas sheet cake, chocolate fudge frosting, moist chocolate sheet cake dessert, Texas sheet cake, Texas sheet cake with buttermilk

Prep Time 20

Cook Time 30

Total Time 50

Servings to 20

Calories 410kcal

Author Cathy Pollak

Equipment

baking dish 9x13 (23×33 cm). This pan gives the cake its intended thickness and allows the frosting to be poured directly over the cake while it's still hot.
Saucepan (medium). Used to simmer the cocoa mixture for the cake and brown the butter for the frosting.
mixing bowls (large) For combining the cake batter and preparing the chocolate frosting.
whisk Helps incorporate the hot cocoa mixture into the batter and makes the frosting smooth.
rubber spatula or offset spatula. For scraping the bowl and spreading the warm frosting evenly over the cake.
Toothpick Checks that the center of the thicker cake is fully baked.

Ingredients

Cake:

2 cups (260 g) all-purpose flour
1½ cups (300 g) granulated sugar
¼ cup (60 g) packed light brown sugar
1 tsp (3 g) kosher salt
1 cup (226 g) unsalted butter
½ cup (40 g) Dutch-process cocoa powder
¾ cup (180 ml) hot brewed coffee
¼ cup (60 ml) water
½ cup (120 ml) buttermilk
2 large eggs room temperature
1 tsp (5 g) baking soda
2 tsps (10 ml) vanilla extract

Brown Butter Chocolate Frosting:

¾ cup (170 g) unsalted butter
⅓ cup (30 g) Dutch-process cocoa powder
⅓ cup (80 ml) buttermilk
3¾ cups (450 g) confectioners' sugar
¾ tsp (2.5 g) kosher salt
1 tsp (5 ml) vanilla extract
¾ cup (100 g) toasted pecans chopped (optional)

Instructions

Preheat the oven to 350°F (175°C). Lightly grease a 9×13-inch (23×33 cm) baking pan.
Whisk together the flour, granulated sugar, brown sugar, and kosher salt in a large mixing bowl. In a medium saucepan, combine the butter, Dutch-process cocoa powder, hot coffee, and water. Cook over medium heat, whisking occasionally, until the butter melts and the mixture reaches a gentle simmer. Continue whisking for about 30 seconds to bloom the cocoa, then remove from the heat.
2 cups (260 g) all-purpose flour, 1½ cups (300 g) granulated sugar, ¼ cup (60 g) packed light brown sugar, 1 tsp (3 g) kosher salt, 1 cup (226 g) unsalted butter, ½ cup (40 g) Dutch-process cocoa powder, ¾ cup (180 ml) hot brewed coffee, ¼ cup (60 ml) water
Pour the hot chocolate mixture over the dry ingredients and whisk until combined, making sure no pockets of dry flour remain. In a separate bowl, whisk together the buttermilk, eggs, baking soda, and vanilla extract. Add to the chocolate batter and whisk until smooth and evenly combined. The batter will be relatively thin and pourable.
½ cup (120 ml) buttermilk, 2 large eggs, 1 tsp (5 g) baking soda, 2 tsps (10 ml) vanilla extract
Pour the batter into the prepared pan and spread evenly. Bake for 25–30 minutes, or until the center springs back lightly when touched and a toothpick inserted into the middle comes out with a few damp cake particles but no wet batter. Because this Texas sheet cake is thicker than the traditional recipe, check the center rather than relying on the appearance of the outer portion of the cake.
Begin preparing the brown butter chocolate frosting during the last 10 minutes of baking so it's warm and ready when the cake comes out of the oven. Melt the butter in a medium saucepan over medium heat. Continue cooking, swirling the pan occasionally, as the butter foams and the milk solids begin turning golden brown. Watch closely once brown specks appear on the bottom of the pan. Remove from the heat when the butter smells toasted and nutty, before the milk solids become dark brown or burn.
¾ cup (170 g) unsalted butter
Immediately whisk the Dutch-process cocoa powder into the browned butter, including the browned milk solids, and stir for about 30 seconds until the cocoa is fully incorporated. Let the mixture cool for 1–2 minutes, then gradually whisk in the buttermilk until smooth and fully incorporated.
⅓ cup (30 g) Dutch-process cocoa powder, ⅓ cup (80 ml) buttermilk
Place the confectioners' sugar and kosher salt in a large mixing bowl, breaking up any lumps. Pour in the warm chocolate mixture, add the vanilla extract, and whisk until the frosting is smooth and thick but still pourable. If necessary, use an immersion blender briefly to smooth out any remaining lumps. The frosting will thicken as it cools, so if it becomes too stiff to pour, whisk in warm water or buttermilk, 1 teaspoon (5 ml) at a time, until it loosens enough to spread. Avoid adding extra confectioners' sugar unless the frosting is unusually thin, since it will continue to firm as it sets.
3¾ cups (450 g) confectioners' sugar, ¾ tsp (2.5 g) kosher salt, 1 tsp (5 ml) vanilla extract
As soon as the cake comes out of the oven, pour the warm chocolate frosting over the hot surface. Use an offset spatula or the back of a spoon to gently spread it across the entire cake, working toward the sides without repeatedly dragging through the frosting. The warmth of the cake helps the frosting spread before it begins to set into a thick fudge-like layer.
Sprinkle with toasted pecans, if using, while the frosting is still soft. Let the cake rest for approximately 20 minutes, or until the frosting has set enough to slice without running. Serve directly from the pan.
¾ cup (100 g) toasted pecans

Notes

Use Dutch-process cocoa powder for the specified chocolate flavor and color. Natural cocoa powder has different acidity and may affect the cake's rise.
The coffee complements the cocoa without making this an intentionally coffee-flavored cake. Hot water can replace the coffee if preferred.
Prepare the frosting toward the end of baking. It thickens as it cools and spreads best while warm.
The pecans are optional. If using them, toast and chop them before preparing the frosting.
Allow the frosting to set for approximately 20 minutes before slicing.
Store covered in a cool room for up to 2 days, or refrigerate for up to 4 days. Bring refrigerated cake to room temperature before serving.
The unfrosted cake can be wrapped tightly and frozen for up to 2 months. Thaw before preparing and applying the frosting.
Nutritional information is provided as a courtesy only and should be construed as an estimate rather than a guarantee. Ingredients can vary, and Noble Pig makes no guarantees to the accuracy of this information.

Nutrition