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Costco Chocolate Cake

Costco Chocolate Cake

Costco Chocolate Cake is a rich, moist dessert layered with smooth chocolate frosting and deep cocoa flavor. This bakery-style cake is perfect for birthdays, parties, or any chocolate lover craving a sweet and creamy treat.
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Prep Time 35 minutes
Cook Time 40 minutes
Cool Time: 15 minutes
Total Time 1 hour 30 minutes
Servings: 16 Slices
Course: Dessert
Cuisine: American
Calories: 780
Ingredients Method

Ingredients
  

For the Cake
  • 2 cups freshly brewed coffee
  • 4 cups sugar
  • 2 cups buttermilk
  • 4 cups all-purpose flour
  • 1 1/2 cups Dutch-processed cocoa powder
  • 1 cup sour cream or Greek yogurt
  • 4 teaspoons baking soda
  • 4 teaspoons vanilla extract
  • 2 teaspoons baking powder
  • 6 large eggs
  • 1 cup vegetable oil
  • 2 teaspoons sea salt
  • 8 ounces dark chocolate melted
For the Frosting
  • 3 cups Dutch-processed cocoa powder
  • 2 tablespoons vanilla extract
  • 16 ounces cream cheese softened
  • 3 cups unsalted butter softened
  • 1/2 cup heavy whipping cream
  • 12 ounces powdered sugar
  • 1 teaspoon salt
For the Ganache (Optional)
  • 1 1/2 cups heavy whipping cream
  • 2 cups dark chocolate chips

Method
 

Step 1: Prepare the Pans
  1. Preheat your oven to 350°F (175°C). Grease and line two 9-inch cake pans with parchment paper.
Step 2: Mix the Dry Ingredients
  1. In a large bowl, whisk together:
  2. Flour
  3. Cocoa powder
  4. Baking soda
  5. Baking powder
  6. Salt
  7. Set aside.
Step 3: Mix the Wet Ingredients
  1. In another large bowl, combine:
  2. Sugar
  3. Eggs
  4. Buttermilk
  5. Sour cream
  6. Vegetable oil
  7. Vanilla extract
  8. Whisk until smooth.
Step 4: Add Coffee and Chocolate
  1. Slowly stir in the hot coffee and melted dark chocolate. The batter will look thin, which is completely normal.
Step 5: Combine Everything
  1. Gradually add the dry ingredients into the wet mixture. Stir gently until fully combined and smooth.
Step 6: Bake the Cakes
  1. Divide the batter evenly between the prepared pans. Bake for 35–40 minutes or until a toothpick inserted into the center comes out mostly clean. Let the cakes cool in the pans for 15 minutes before transferring them to a wire rack.
Step 7: Make the Frosting
  1. In a large bowl, beat the butter and cream cheese until fluffy.
  2. Add:
  3. Cocoa powder
  4. Powdered sugar
  5. Vanilla
  6. Salt
  7. Heavy cream
  8. Beat until creamy and smooth.
Step 8: Prepare the Ganache (Optional)
  1. Heat the heavy cream until steaming but not boiling. Pour over the chocolate chips and let sit for 2 minutes. Stir until smooth and glossy.
Step 9: Assemble the Cake
  1. Place one cake layer on a serving plate. Spread a thick layer of frosting on top. Add the second layer and frost the entire cake. Drizzle ganache over the top if desired.