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Copycat Costco Vanilla Cake Recipe

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★★★★★

4.9 from 146 reviews

This Copycat Costco Vanilla Cake replicates the popular store-bought favorite with layers of moist vanilla cake, creamy vanilla mousse filling, and rich buttercream frosting. Perfect for celebrations or any occasion, this recipe offers a deliciously fluffy texture and classic vanilla flavor using simple ingredients and straightforward baking methods.

Ingredients

Scale

Cake Ingredients

  • 2 1/2 cups plus 2 tablespoons cake flour
  • 1 1/2 cups plus 2 tablespoons granulated sugar
  • 1 tablespoon baking powder
  • 3/4 teaspoon fine salt
  • 3/4 cup unsalted butter, very soft
  • 4 large egg whites, room temperature
  • 1 large egg yolk, room temperature
  • 1 tablespoon vanilla extract
  • 1 cup buttermilk, room temperature

Buttercream Ingredients

  • 2 tablespoons water
  • 2 tablespoons cornstarch
  • 1 cup unsalted butter, very soft
  • 1/2 cup vegetable shortening, room temperature
  • 4 cups powdered sugar
  • 1/2 teaspoon fine salt
  • 1 tablespoon vanilla extract
  • 3 to 4 tablespoons whole milk or heavy cream, room temperature

Assembly Ingredients

  • Copycat Costco Vanilla Mousse (prepared separately)
  • Sprinkles for garnish

Instructions

  1. Prepare the cake pans: Preheat your oven to 350°F (175°C). Spray two 8-inch cake pans with baking spray, then line the bottoms with parchment paper to ensure easy release later.
  2. Mix dry cake ingredients: In a large mixing bowl, combine the cake flour, granulated sugar, baking powder, and fine salt thoroughly.
  3. Add butter to dry mix: With your mixer on low speed, gradually add the very soft unsalted butter to the dry ingredients. The mixture will turn sandy and crumbly, which is expected. Continue beating for 1 to 2 minutes, scraping the sides and bottom of the bowl to ensure even mixing.
  4. Incorporate egg whites and yolk: Slowly add the egg whites one at a time into the batter, beating well after each addition. Then, beat in the single egg yolk along with the vanilla extract until fully combined.
  5. Add buttermilk gradually: With the mixer on low speed, slowly add the buttermilk in three separate additions. Beat for 1 to 2 minutes after each addition to ensure a smooth, well-mixed batter.
  6. Bake the cake layers: Divide the batter evenly between the prepared cake pans. Bake for approximately 26 to 30 minutes or until the cakes are golden on top and a toothpick inserted into the center comes out mostly clean with a few moist crumbs.
  7. Cool the cakes: Allow the cake layers to cool in the pans for 5 minutes. Then invert each cake onto a wire rack to cool completely. Remove the parchment paper gently. If not assembling immediately, wrap the cooled cakes in plastic wrap and refrigerate.
  8. Prepare the buttercream frosting: In a small bowl, whisk together the water and cornstarch until smooth, then set aside. In a large bowl, beat the unsalted butter and vegetable shortening with a mixer on medium speed until light and fluffy, about 3 to 4 minutes. Add the cornstarch mixture and mix to combine.
  9. Finish buttercream: Gradually add the powdered sugar on low speed, scraping down the bowl as necessary. Add the fine salt and vanilla extract, mixing thoroughly. If the frosting is too thick, add whole milk or heavy cream one tablespoon at a time until reaching the desired consistency.
  10. Level the cakes: If the cake layers have domed tops, use a serrated knife to level them for easier stacking.
  11. Assemble the cake: Place a small amount of frosting on a cake board to secure the first cake layer. Pipe a ring of buttercream frosting around the edge of the layer using a pastry bag to create a barrier for the mousse filling.
  12. Add mousse filling: Spoon or pipe the prepared Copycat Costco Vanilla Mousse into the ring, spreading it evenly without spilling over.
  13. Top and frost: Carefully place the second cake layer on top of the mousse. Coat the outside of the cake with the remaining buttercream using an offset spatula. Smooth out the frosting and remove any excess.
  14. Decorate and serve: Garnish the finished cake with sprinkles as desired. Slice and enjoy this rich, creamy copycat vanilla cake.

Notes

  • Make sure all wet ingredients—eggs, buttermilk, butter—are at room temperature for best batter consistency.
  • Use cake flour for a tender crumb; substitute with all-purpose flour plus cornstarch if necessary.
  • Buttercream can be adjusted for sweetness and texture by modifying powdered sugar and milk quantities.
  • Refrigerate assembled cake for a few hours before serving to let the mousse and frosting set nicely.
  • Ensure cakes cool completely before frosting to prevent melting.

Keywords: Costco vanilla cake copycat, vanilla layer cake, buttercream frosting, mousse cake, homemade vanilla cake, classic vanilla dessert

Find it online: https://topreci.com/copycat-costco-vanilla-cake-recipe/