Rich chocolate cake, velvety mousse, and a silky chocolate frosting—this Costco Tuxedo Cake Recipe brings home the magic of that famous store-bought dessert.
You ever have one of those desserts that just haunt you? Like, you take one bite, and suddenly it’s all you can think about? That was me with Costco’s Tuxedo Cake. I was at a party, not even particularly hungry, and someone handed me a slice.
Game over.
The rich, fudgy cake, the creamy mousse, the perfectly smooth frosting—it was everything I never knew I needed. And because I have zero self-control when it comes to chocolate, I immediately went to Costco and bought a whole one. Did I share it? Barely. But the problem with buying a Costco cake is… well, it’s Costco-sized. You either eat cake for breakfast, lunch, and dinner (not saying I did, but also not saying I didn’t), or you start pawning slices off on unsuspecting friends.
That’s when it hit me—what if I could make it myself? Same taste, smaller portions, and maybe even better? So I got to work. After some trial and error (which, let’s be honest, wasn’t the worst thing in the world because, hello, taste tests), I nailed it. And now? Now, I get to share this ridiculously indulgent homemade Costco Tuxedo Cake Recipe with you.
So let’s do this—you get the cake, and I get to live vicariously through your chocolate-induced happiness.
Why You’ll Love This Costco Tuxedo Cake Recipe?
- It’s the Same Cake, but Fresher & Homemade – No preservatives, no waiting in line at Costco, no questionable impulse purchases (just me?).
- Easy but Impressive – It looks fancy, but it’s actually super simple thanks to a few baking shortcuts.
- Chocolate on Chocolate on Chocolate – Layers of it. If you love chocolate, this is your dream cake.
- Perfect for Any Occasion – Special celebration? Treat-yourself Tuesday? It fits any excuse.
Ingredient Notes:
Every great cake has a dream team of ingredients. Let’s break it down:
- Chocolate Fudge Cake Mix – Listen, I love homemade cakes, but sometimes a boxed mix just works. With a few tweaks, no one will ever know.
- Eggs (+ One Extra) – That extra egg makes the cake richer and more indulgent. Trust me, don’t skip it.
- Butter Instead of Oil – Oil is fine, but melted butter gives the cake that next-level flavor.
- Milk Instead of Water – More moisture, more richness, more magic.
- Heavy Whipping Cream + Instant Pudding Mix – The secret to a thick, stable mousse layer. No weird soupy fillings here.
- Corn Syrup – Keeps the frosting glossy and smooth. It’s a small ingredient, but it matters.
- Semisweet Chocolate Chips – Because there’s no such thing as too much chocolate.
Pro Tip:
If you want an even deeper, richer chocolate flavor, swap regular cocoa powder for dark cocoa powder. It’s what bakeries do for that ultra-chocolatey kick.
How To Make Costco Tuxedo Cake?
Step 1: Bake the Cake
Preheat your oven to 350°F. Grease two 9-inch cake pans.
In a large bowl, mix your cake mix, eggs (plus the extra one!), melted butter (instead of oil), and milk (instead of water). Stir until smooth.
Divide the batter between your pans and bake for 20 minutes. Use the classic toothpick test—if it comes out clean, you’re golden. Let the cakes cool completely before moving on.
Step 2: Make the Chocolate Mousse
While the cakes cool, let’s get this mousse situation sorted.
In a bowl, beat heavy whipping cream with instant chocolate pudding mix until thick and fluffy. That’s it! No complicated steps, no gelatin—just creamy, chocolatey goodness.
Once your cakes are cool, place one layer on a cake stand. Spread all the mousse on top, then gently place the second cake layer over it.
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Step 3: The Frosting Situation
Melt your chocolate chips and corn syrup in a microwave-safe bowl, heating in 30-second bursts and stirring between each one. Let it cool slightly (but don’t let it harden).
Meanwhile, in another bowl, beat butter, powdered sugar, cocoa, and vanilla until light and fluffy. Slowly mix in the melted chocolate.
Now, frost the cake! Spread that silky frosting all over, then pipe or swirl the edges if you’re feeling fancy.
Step 4: The Costco Touch (Optional but Fun)
If you really want it to look like the original, take the cake tops you sliced off earlier, crumble them finely, and press them onto the sides of the cake. It gives that classic store-bought but actually homemade look.
Storage Options:
- Fridge: Store in an airtight container for up to 5 days.
- Freezer: Wrap individual slices and freeze for up to 3 months. Just thaw in the fridge when you’re ready for a chocolate fix.
Variations and Substitutions:
Want to switch things up? Here are some fun ways to tweak this cake:
- Make It Dark Chocolate – Swap in dark cocoa powder and dark chocolate chips for a more intense flavor.
- Add Espresso Powder – Just a teaspoon in the batter or frosting enhances the chocolate. Trust me on this one.
- Use a Different Frosting – Not a buttercream fan? Try a whipped ganache for a silkier finish.
- Nutty Crunch – Fold chopped hazelnuts or almonds into the mousse for extra texture.
What to Serve with Costco Tuxedo Cake?
This cake is rich, so pairing it with something light makes it even better:
- Whipped Cream – A simple, fluffy contrast.
- Fresh Berries – Raspberries or strawberries cut through the sweetness perfectly.
- Vanilla Ice Cream – Classic for a reason.
- Strong Coffee or Espresso – Because chocolate and coffee were meant to be together.
Frequently Asked Questions:
Can I make this cake ahead of time?
Yep! You can bake the cake layers a day ahead and store them wrapped. The mousse and frosting can be made the same day or a few hours in advance.
What if I don’t have instant pudding mix?
No problem! Mix 2 tablespoons cornstarch, ½ cup sugar, and 3 tablespoons cocoa powder—it works just as well.
Can I use a different cake mix?
Absolutely! Any chocolate cake mix will work, but fudge cake mix gives the richest flavor and texture.
And that’s it! Your very own homemade Costco Tuxedo Cake Recipe—same great taste, freshly made, and way more satisfying. Whether you’re baking it for a special occasion or just because (let’s be real, do we even need an excuse?), this cake is a total winner.
Try it out and let me know how it goes! Did you make any fun tweaks? Devour it in one night? No judgment. Drop a comment—I’d love to hear all about it!
<Remember it later>
Planning to try this recipe soon? Pin it for a quick find later!
<Remember it later>
Planning to try this recipe soon? Pin it for a quick find later!
Keep the Flavor Coming – Try These:
Costco Tuxedo Cake Recipe
Ingredients
For the Cake:
- 1 box 13.5 oz chocolate fudge cake mix
- Eggs as directed on the cake mix box + 1 additional egg
- Butter substituting the amount of oil listed on the box
- Milk substituting the amount of water listed on the box
For the Chocolate Mousse:
- 3 cups heavy whipping cream
- 1 box 5.9 oz instant chocolate pudding mix
For the Chocolate Frosting:
- 2 cups unsalted butter softened
- 2 cups powdered sugar
- 1 cup unsweetened cocoa powder
- 1 teaspoon vanilla extract
- ½ cup corn syrup
- 4 cups semisweet chocolate chips
Instructions
Prepare the Cake Layers
- Preheat the oven to 350°F (175°C). Grease and lightly flour two 9-inch cake pans.
- In a large mixing bowl, combine the cake mix, eggs, melted butter (in place of oil), and milk (in place of water). Stir until smooth and fully incorporated.
- Divide the batter evenly between the prepared cake pans.
- Bake for approximately 20 minutes, or until a toothpick inserted into the center comes out clean.
- Remove from the oven and allow the cakes to cool in their pans for 10 minutes before transferring them to a wire rack to cool completely.
- Once cooled, trim the rounded tops to create flat layers. Reserve the trimmed portions for later use.
Prepare the Chocolate Mousse
- In a large mixing bowl, combine the heavy whipping cream and instant chocolate pudding mix.
- Using an electric mixer, beat on medium speed until the mixture thickens and forms soft peaks.
- Place one cooled cake layer on a serving plate.
- Spread the prepared mousse evenly over the cake layer, ensuring a smooth surface.
- Gently place the second cake layer on top.
Prepare the Chocolate Frosting
- In a microwave-safe bowl, melt the chocolate chips and corn syrup in 30-second intervals, stirring between each until fully melted and smooth. Set aside to cool slightly.
- In a separate large bowl, beat together butter, powdered sugar, cocoa powder, and vanilla extract using an electric mixer until light and fluffy.
- Slowly add the melted chocolate mixture, continuing to beat until the frosting is well combined and silky in texture.
Assemble and Decorate
- Evenly frost the top and sides of the cake using an offset spatula or knife.
- If desired, transfer some frosting to a piping bag and decorate the edges for a professional finish.
- To replicate Costco’s signature appearance, finely crumble the reserved cake trimmings and gently press them onto the sides of the frosted cake.
- For the final touch, use a fork to create decorative swirls or squiggles on the frosting.
Notes
- Cake Mix Substitute: Use a high-quality gluten-free chocolate cake mix in place of the regular boxed mix. Ensure it has a similar weight (13.5 oz) for accurate proportions.
- Thickening Agent for Mousse: Some instant pudding mixes contain gluten. Choose a certified gluten-free pudding mix or make homemade chocolate pudding with cornstarch and cocoa powder.
- Chocolate Chips: Confirm that the semisweet chocolate chips are gluten-free, as some brands process them in facilities that handle gluten-containing products.
I’m Bitty, owner of nodashofgluten.com, where I share simple, delicious recipes for all tastes, including gluten-free. Check out my “About Me” page for more info!
