Costco Chocolate Cake Recipe

This Costco Chocolate Cake is a decadent and rich recipe, which is made with a fudgy cake, a light chocolate mousse, and a silky chocolate frosting. It’s the perfect celebration cake, ready in about 55 minutes plus cooling time.

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Costco Chocolate Cake Recipe Ingredients

For the Cake:

• 1 (13.5 ounce) box Chocolate fudge cake mix
• Eggs (the number called for on the box, plus 1 extra)
• Butter, melted (the same amount as the oil called for on the box)
• Milk (the same amount as the water called for on the box)

For the Mousse Filling:

• 3 cups heavy whipping cream
• 1 (5.9 ounce) box instant chocolate pudding mix

For the Frosting:

• 4 cups semisweet chocolate chips
• ½ cup corn syrup
• 2 cups (4 sticks) butter, softened
• 2 cups powdered sugar
• 1 cup unsweetened cocoa powder
• 1 teaspoon vanilla extract

How To Make Costco Chocolate Cake

1. Make and Bake the Cake: Preheat your oven to 350°F. Grease two 9-inch round cake pans. In a large bowl, prepare the cake mix according to the package directions, but with the following substitutions: use one extra egg, use melted butter instead of oil, and use milk instead of water.
2. Bake and Cool: Divide the batter evenly between the two prepared pans. Bake for about 20 minutes, or until a toothpick inserted into the center comes out clean. Let the cakes cool completely.
3. Make the Mousse Filling: In a large bowl, combine the heavy whipping cream and the dry instant pudding mix. Beat with an electric mixer on high speed until the mixture is thick, fluffy, and holds its shape.
4. Level the Cakes and Assemble: Once the cakes are cool, use a long, serrated knife to level them by slicing off the rounded tops. Set the cake tops aside. Place one cooled cake layer on a cake platter and spread all of the mousse filling over the top. Place the second cake layer on top of the mousse.
5. Start the Frosting: In a microwave-safe bowl, combine the chocolate chips and corn syrup. Microwave in 30-second intervals, stirring between each, until the chocolate is completely melted and smooth. Set aside to cool slightly, but not harden.
6. Finish the Frosting: In a separate large bowl, use an electric mixer to whip the softened butter, powdered sugar, cocoa powder, and vanilla until combined. Beat in the cooled chocolate and corn syrup mixture until the frosting is smooth and silky.
7. Frost and Decorate: Frost the top and sides of the assembled cake with the chocolate frosting. For the classic Costco look, crumble the reserved cake tops you sliced off earlier and gently press the crumbs into the sides of the cake. Use a fork to make squiggly lines across the top of the frosting.

Recipe Tips

• How do I make the cake extra moist? The recipe’s “doctored” cake mix method—using milk instead of water, butter instead of oil, and an extra egg—is the secret to an incredibly moist and rich cake that tastes homemade.
• How do I get a neat, professional look? For easier and neater frosting, chill the assembled cake (with the mousse filling) in the refrigerator for about 30 minutes before you start frosting. This helps the layers stay in place and prevents crumbs from mixing into the frosting.
• What if I ate the cake tops? If you don’t have the cake scraps for the crumb coating, you can crush up Oreo cookies (without the cream filling) to get a similar look and texture for the sides of the cake.
• Can I make this ahead of time? Yes. For the best results, bake the cake layers a day in advance and store them wrapped at room temperature. Assemble the cake with the fresh mousse and frosting on the day you plan to serve it.

What To Serve With Costco Chocolate Cake

This decadent, multi-layered chocolate cake is a showstopper that needs very little accompaniment.

• A tall glass of cold milk.
• A hot cup of black coffee or an espresso.
• A scoop of vanilla bean ice cream.
• A side of fresh raspberries to cut the richness.

How To Store Costco Chocolate Cake

Store: Because of the mousse filling and buttercream frosting, this cake must be stored in the refrigerator. Cover it with a cake dome or plastic wrap and it will keep well for up to 5 days.

Costco Chocolate Cake Nutrition Facts

• Calories: 1369kcal
• Protein: 11g
• Fat: 98g
• Carbohydrates: 122g
• Sugar: 88g

Nutrition information is estimated and may vary based on ingredients and cooking methods used.

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