Texas Sheet Cake

Get ready for the chocolate cake that feeds an army and tastes like pure bliss!

This Texas-sized beauty delivers rich, fudgy chocolate goodness with a glossy icing that gets poured on while the cake’s still warm.

We’re talking about serious comfort food territory here.

What makes this cake legendary?

That thin layer of intensely chocolatey cake paired with an icing so good you’ll want to eat it with a spoon.

The secret is in the technique – boiling that cocoa mixture creates an incredibly moist crumb, while the warm cake absorbs every drop of that silky icing.

One bite and you’ll understand why this recipe has been passed down through generations of Texas kitchens.

Ingredients

For the Cake:

• 2 cups all-purpose flour
• 2 cups white sugar
• 1 teaspoon baking soda
• ½ teaspoon salt
• ½ cup sour cream
• 2 eggs
• 1 cup butter
• 1 cup water
• 5 tablespoons unsweetened cocoa powder

For the Icing:

• 6 tablespoons milk
• 5 tablespoons unsweetened cocoa powder
• ½ cup butter
• 4 cups confectioners’ sugar
• 1 teaspoon vanilla extract
• 1 cup chopped walnuts (optional)

Steps

1. Gather all ingredients and preheat your oven to 350°F (175°C). Generously grease and flour a 10×15-inch jelly roll pan – this prevents sticking and ensures easy removal. Don’t skip the flouring step, as this cake can be stubborn without it.
2. Make the cake base by combining flour, sugar, baking soda, and salt in a large mixing bowl. Whisk these dry ingredients together until evenly distributed, then beat in the sour cream and eggs using an electric mixer on medium speed until just combined. The mixture will look thick and slightly lumpy at this stage – that’s perfect.
3. Create the chocolate base by melting 1 cup butter in a medium saucepan over low heat. Once melted, stir in 1 cup water and 5 tablespoons cocoa powder, whisking constantly to prevent lumps. Bring this mixture to a rolling boil, then immediately remove from heat. The boiling step is crucial – it blooms the cocoa and creates that signature fudgy texture.
4. Allow the cocoa mixture to cool for 2-3 minutes (it should still be warm but not scalding), then gradually stir it into the flour mixture until completely blended. The batter should be smooth and pourable. Pour immediately into your prepared pan, spreading evenly to all corners.
5. Bake for 18-22 minutes, or until a toothpick inserted in the center comes out with just a few moist crumbs. Don’t overbake – this cake is meant to be tender and slightly fudgy. Start checking at 18 minutes as oven temperatures vary.
6. While the cake bakes, prepare the icing by combining milk, 5 tablespoons cocoa powder, and ½ cup butter in a large saucepan over medium heat. Whisk constantly and bring to a full boil – you’ll see vigorous bubbling across the entire surface. Remove from heat immediately.
7. Working quickly, whisk in confectioners’ sugar and vanilla until completely smooth. The icing should be glossy and pourable but not too thin. Fold in walnuts if using. This icing sets quickly, so work fast.
8. Pour the warm icing over the warm cake immediately after removing from oven. Use an offset spatula to spread evenly, working quickly before the icing begins to set. The warm cake will absorb some of the icing, creating that perfect marriage of cake and frosting.
9. Allow to cool completely before cutting – this takes about 2 hours at room temperature. The icing will form a beautiful glossy shell while staying tender underneath.

Smart Swaps

• Greek yogurt instead of sour cream (1:1 ratio) – adds protein without changing texture
• Coconut oil for butter in cake (use solid, not melted) – creates extra moisture

Make It Diabetes-Friendly

Replace 2 cups white sugar with 1½ cups erythritol blend (reduces carbs by 75% per serving, from 45g to 11g carbs). Substitute 4 cups confectioners’ sugar in icing with 2 cups powdered erythritol plus 2 tablespoons cornstarch for smooth texture. This modification cuts total carbs from 48g to 14g per serving. Pair with unsweetened whipped cream and fresh berries to further slow glucose absorption. Consider cutting into 48 smaller squares instead of 32 for better portion control.

Pro Tips

• Use room temperature eggs for smoother mixing and better texture
• Sift confectioners’ sugar before adding to icing to prevent lumps
• Store covered at room temperature for up to 5 days – the flavors actually improve overnight