There’s something undeniably comforting about a big, chocolatey slab of cake that practically melts in your mouth—and Texas Sheet Cake delivers exactly that. I still remember the first time I tasted this southern classic at a friend’s family picnic. The afternoon sun was beating down, paper plates were flying around, and that rich chocolate aroma wafted from the dessert table like a siren song. One bite, and I was hooked. Years later, I’ve perfected my go-to version: ultra-moist from sour cream in the batter, topped with a glossy, walnut-studded chocolate frosting. It’s the kind of make-ahead dessert that’s always the first to disappear at potlucks, family gatherings, or casual weeknight dinners when you want something sweet and simple.
What I love most about this Texas Sheet Cake is how hands-off it is—no need for multiple bowls, layer stacking, or fancy piping bags. You simmer everything in one saucepan, pour it into a sheet pan, bake, and top right in the same vessel. If you asked me to compare it to something, I’d say it’s a cross between a fudgy brownie and a tender, moist cake, only on a grand scale. Plus, that walnut-studded frosting? It’s just the right crunch to balance all that softness.
Below, you’ll find everything you need to whip up this show-stopping cake. I suggest gathering your ingredients first, because once you start, this comes together in a flash.
Ingredients
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1 cup margarine
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1 cup water
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4 tablespoons cocoa powder
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2 cups all-purpose flour
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2 large eggs, beaten
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1 teaspoon baking soda
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2 cups granulated sugar
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½ cup sour cream
Steps
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Preheat & Prepare the Pan
Preheat your oven to 375°F. Grab a 10×15×2-inch baking pan and butter and flour it—alternatively, a quick spray of nonstick cooking spray works wonders. Lining it well ensures your cake slides right out when it’s time to serve. -
Simmer the Base
In a large, heavy-bottomed saucepan set over medium heat, combine the margarine, water, and cocoa powder. Stir constantly until the margarine melts and the mixture comes to a rolling boil. You’ll notice the cocoa fully dissolves, yielding a silky, dark liquid—that’s your flavor foundation. -
Brief Cool-Down
Remove the pan from heat and let the mixture rest for 2–3 minutes. This brief pause cools it just enough so you won’t scramble the eggs in the next step, yet keeps it warm enough to blend beautifully with sugar and sour cream. -
Mix in the Dry & Wet
Return to the saucepan (off the heat) and whisk in the flour, beaten eggs, baking soda, granulated sugar, and sour cream. At first, it looks like a hot chocolate soup, but keep stirring until the batter is smooth and uniform. The sour cream ensures that ultra-moist crumb—don’t skip it! -
Transfer & Bake
Pour the batter evenly into your prepared sheet pan, using a spatula to coax it into the corners. Slide it onto the center rack and bake for 22–25 minutes. You’re looking for a toothpick inserted in the center to come out clean, but resist the temptation to overbake—it should still be tender.
Frosting, Finishing & Helpful Tips
Now that your cake has had its moment to rest, it’s time for the pièce de résistance—the glossy, chocolate–walnut frosting that turns a humble sheet cake into a showstopper. In just a few simple steps, you’ll transform that tender cake base into a luscious treat with a satisfyingly smooth top studded with crunchy nuts. Let’s dive right in.
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Gently Reheat Your Frosting Base
In the same (or a clean) medium saucepan, combine ½ cup margarine, 6 tablespoons milk, and 4 tablespoons cocoa powder. Place over medium heat and stir constantly until the margarine melts and the mixture comes to a boil. You’ll see it darken and thicken just slightly—this heat helps the powdered sugar dissolve completely later on. -
Incorporate the Dry Ingredients
Remove the pan from the heat immediately (to avoid scorching) and stir in 3½ cups powdered sugar and 1 teaspoon vanilla extract. At first, the mixture will look stiff and pasty; that’s normal. Keep stirring briskly—by the time you’re done, you’ll have a smooth, spreadable frosting. -
Add the Crunch
Fold in 1 cup chopped walnuts (or your preferred nut). The residual heat from the frosting will toast them ever so slightly, bringing out their toasty flavor. If you’re going nut-free, swap in toasted pecans or simply omit them for pure chocolate bliss. -
Spread While Warm
Pour the warm frosting evenly over the cake, using a rubber spatula to coax it right to the edges. Work quickly—the frosting sets as it cools, and you want those swirls and swipes to look smooth and intentional. -
Allow to Set
Let the cake sit at room temperature for at least 1 hour, or until the frosting has firmed up enough to slice neatly. If your kitchen is on the cooler side and the frosting firms too fast (resulting in tear-through edges), loosely cover with foil to trap a bit of warmth, or pop the frosting back on the stovetop for 15–20 seconds to soften before spreading.
Pro Tips & Variations
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Ultra-Moist Hack: For an extra-rich crumb, replace half the sour cream in the batter with plain Greek yogurt. You’ll notice a subtle tang and even more moisture.
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Nut-Free Version: Simply omit the walnuts or swap in sunflower seeds for a lightly nutty crunch.
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Make-Ahead Convenience: You can bake the cake a day in advance—cover tightly with foil and leave the frosting until just before serving. This way, you avoid any frosting “sweat” and still have that fresh, glossy sheen.
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Flavor Twists: Stir a pinch of espresso powder into the frosting base for an intensified chocolate flavor. Alternatively, add ½ teaspoon ground cinnamon to the batter for a warm, spicy undertone.
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Perfect Slices: Use a sharp knife dipped in hot water (and wiped dry) for clean, professional-looking squares. Reheat the knife between cuts for best results.
FAQ & Conclusion
Q1: Can I freeze Texas Sheet Cake?
Absolutely! Once the cake is completely cooled and the frosting is set, wrap the entire pan tightly with plastic wrap and then aluminum foil to prevent freezer burn. It will keep well for up to 2 months. Thaw overnight in the refrigerator, then bring to room temperature before serving so the frosting softens back to its glossy perfection.
Q2: How should I store leftovers?
Store any uneaten cake in an airtight container at room temperature for up to 3 days. If your kitchen is warm, you can refrigerate it—just let slices sit out for 15–20 minutes before serving so the frosting regains its shine and the cake softens up.
Q3: I don’t have sour cream—what can I use instead?
Plain Greek yogurt is my go-to swap: use it in equal measure for sour cream. It brings the same tang and moisture. If neither is on hand, a mix of ¼ cup melted butter plus ¼ cup plain yogurt can work, though the texture will be slightly different.
Q4: Can I make the cake dairy-free?
To go dairy-free, substitute the margarine in both cake and frosting with a plant-based butter alternative, and use your favorite non-dairy milk (soy, almond, or oat) in place of regular milk. The cake will still be rich and chocolatey—promise!
Q5: What if I want a nut-free version?
Skip the walnuts entirely or replace them with toasted pepitas or sunflower seeds for a nut-free crunch. You can also swirl in a handful of mini chocolate chips for a playful twist that’s safe for those with nut allergies.
Q6: How can I make the chocolate flavor more intense?
Stir in 1–2 teaspoons of instant espresso powder to both the cake batter and the frosting base. Coffee amplifies chocolate’s depth without adding any overt “coffee” taste. It’s my secret weapon for a richer, more complex flavor.
Q7: Why did my frosting set too quickly?
Frosting can firm up fast in a cool kitchen. To avoid this, work in small sections—spread a little at a time and then move on. If it begins to clump, gently rewarm it on the stovetop for 10–15 seconds, stir until smooth, and continue.
Conclusion
There you have it—your ultimate guide to baking, frosting, and enjoying the best Texas Sheet Cake around. From its one-pan simplicity to the ultra-moist crumb and glossy walnut frosting, this recipe checks every box for an easy yet impressive dessert. Whether you’re feeding a crowd at a family reunion or simply craving chocolate on a cozy weeknight, this sheet cake delivers. I hope these tips, tricks, and FAQs help you bake with confidence and creativity. Don’t forget to share your own variations—maybe you’ll add a sprinkle of sea salt or swirl in peanut butter—and let me know how it turns out in the comments below. Happy baking!
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Texas Sheet Cake
Description
A rich, chocolatey cake baked in a thin sheet pan, topped with a glossy walnut-studded frosting. Ultra-moist from sour cream in the batter, it’s the perfect make-ahead dessert for potlucks or family gatherings.
Ingredients
1 cup margarine
1 cup water
4 tablespoons cocoa powder
2 cups all-purpose flour
2 large eggs, beaten
1 teaspoon baking soda
2 cups granulated sugar
½ cup sour cream
For the frosting
½ cup margarine
6 tablespoons milk
4 tablespoons cocoa powder
1 cup chopped walnuts (optional)
3½ cups powdered sugar
1 teaspoon vanilla extract
Instructions
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Preheat the oven to 375°F. Butter and flour a 10×15×2-inch baking pan or spray it with nonstick spray.
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In a large saucepan over medium heat bring the margarine, water and cocoa powder to a rolling boil.
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Remove the pan from the heat and let the mixture cool for 2–3 minutes.
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Whisk in the flour, beaten eggs, baking soda, granulated sugar and sour cream until the batter is smooth and uniform.
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Pour the batter evenly into the prepared pan.
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Bake on the center rack for 22–25 minutes, or until a toothpick inserted in the center comes out clean.
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Allow the cake to cool in the pan for 10–15 minutes while you make the frosting.
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For the frosting, combine margarine, milk and cocoa powder in a saucepan and bring to a boil.
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Remove from heat and immediately stir in the chopped walnuts, powdered sugar and vanilla until the frosting is smooth and spreadable.
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Pour the warm frosting over the cake and spread evenly with a spatula.
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Let the cake sit at room temperature until the frosting is set, about 1 hour, then cut into squares to serve.
Notes
Leftover cake can be stored in an airtight container at room temperature for up to 3 days.
For a nut-free version omit the walnuts or substitute toasted pecans.
To make the cake even more moist, swap half the sour cream for plain Greek yogurt.
If your kitchen is cool and the frosting firms too quickly, warm it briefly before spreading.
