Name: Texas Sheet Cake Recipe
Prep time: 15 min
Cook time: 22 min
Total time: 45 min
Ingredients: 1 cup margarine; 1 cup water; 4 tablespoons cocoa powder; 2 cups all-purpose flour; 2 large eggs (slightly beaten); 1 teaspoon baking soda; 2 cups granulated sugar; 0.5 cup sour cream; 0.5 cup margarine; 6 tablespoons milk; 4 tablespoons cocoa powder; 1 cup chopped walnuts; 3.5 cups powdered sugar; 1 teaspoon vanilla extract

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Rich, moist, and effortlessly crowd-pleasing, this chocolate walnut sheet cake is a dessert built for sharing—though you might be tempted to keep it all to yourself. The chocolate cake base is tender with a velvety crumb, while the warm, fudgy frosting is laced with chopped walnuts for a textural contrast that elevates every bite. It’s nostalgic in the best way: the kind of cake that brings to mind bake sales, potlucks, and family dinners, but with a flavor profile that holds its own among more elaborate desserts.

Best of all, this recipe is straightforward—no need for multiple mixing bowls or complicated techniques. The cake and frosting both come together in saucepans on the stove, making cleanup easier and preparation more streamlined. Whether you’re baking for a casual get-together or just craving something chocolatey and comforting, this is a solid go-to that delivers every time.

Why Use Sour Cream?

Sour cream might seem like an unexpected addition, but it’s a quiet hero in this recipe. It brings moisture and a slight tanginess that balances the richness of the chocolate, keeping the cake soft for days without turning soggy. If you’re out of sour cream, plain Greek yogurt is an easy substitute that maintains the same creamy texture.

A Closer Look at the Ingredients

Margarine – Used in both the cake and the frosting, margarine gives a soft, tender crumb and a buttery mouthfeel. If you prefer, you can substitute unsalted butter for a slightly richer flavor.

Cocoa Powder – Opt for unsweetened cocoa powder for that deep chocolate flavor. It’s melted into the liquid ingredients rather than dry-mixed, enhancing the cake’s fudginess.

Sour Cream – Adds moisture and depth. Greek yogurt is a suitable swap, or you can use buttermilk in a pinch (just reduce the water slightly).

Chopped Walnuts – Stirred into the frosting, they add a pleasant crunch and nutty contrast. Pecans are a good alternative if walnuts aren’t your favorite.

Powdered Sugar – Essential for the frosting’s structure, this dissolves easily and contributes to the glossy finish when poured over the warm cake.

Vanilla Extract – A small amount enhances the chocolate and rounds out the frosting’s flavor.

Let’s Bake: Step-by-Step Instructions

1. Preheat and Prep the Pan
Start by preheating your oven to 375°F. Grease and flour a 10″x15″ baking pan—this helps the cake release cleanly after baking.

2. Make the Cake Batter
In a large saucepan, combine 1 cup of margarine, 1 cup of water, and 4 tablespoons of cocoa powder. Bring this mixture to a gentle boil, stirring occasionally until smooth and glossy. Once it bubbles, remove it from the heat and let it cool slightly—about 5 minutes should do.

Next, add the dry and wet ingredients directly into the saucepan: 2 cups of flour, 2 cups of granulated sugar, 1 teaspoon of baking soda, 2 slightly beaten eggs, and ½ cup of sour cream. Stir everything together until the batter is uniform with no visible flour pockets. The batter should be pourable and smooth.

3. Bake the Cake
Pour the batter into your prepared pan and use a spatula to smooth the top. Bake for about 22 minutes, or until the cake springs back lightly when touched and a toothpick inserted into the center comes out clean. Avoid overbaking—it should stay moist.

4. Prepare the Frosting While the Cake Bakes
In another saucepan, melt ½ cup of margarine with 6 tablespoons of milk and 4 tablespoons of cocoa powder. Let it come to a gentle boil, stirring frequently. Once it’s bubbling, take it off the heat.

Immediately stir in 3½ cups of powdered sugar, 1 teaspoon of vanilla extract, and 1 cup of chopped walnuts. Beat the mixture until smooth and thick, with a glossy consistency that’s easy to pour.

5. Frost the Cake While Warm
As soon as the cake comes out of the oven, pour the warm frosting over it. Spread it gently with a spatula if needed—it should glide easily across the surface. The warmth of the cake helps the frosting meld into the top layer, creating a seamless, fudgy finish.

Let the cake cool at room temperature until the frosting is set and the cake is sliceable.

Serving Suggestions

This cake is best enjoyed at room temperature, where the flavors and textures shine. For a richer experience, serve it with a scoop of vanilla ice cream or a dollop of whipped cream. It also pairs well with strong coffee or black tea to balance the sweetness.

Storing and Making Ahead

Storage
Once cooled, cover the cake tightly with foil or plastic wrap. It will keep well at room temperature for up to 3 days. For longer storage, refrigerate it—just allow it to come to room temperature before serving for best texture.

Freezing
You can freeze the cake (either whole or in squares) for up to a month. Wrap it in plastic, then foil, and thaw overnight in the fridge before enjoying.

Repurposing Leftovers
Leftover slices can be crumbled over ice cream, layered into a trifle with whipped cream and fruit, or gently reheated and topped with espresso for a makeshift mocha cake.

This classic chocolate walnut sheet cake is a reminder that simple, timeless recipes often yield the most satisfying results. It’s versatile, reliable, and deeply chocolatey—everything you want in a homemade dessert.