Ingredients
For the Vanilla Cake
2½ cups all-purpose flour
2½ teaspoons baking powder
½ teaspoon salt
1 cup unsalted butter, softened
1½ cups granulated sugar
4 large eggs, room temperature
1 tablespoon pure vanilla extract
1 cup whole milk, room temperature
½ cup sour cream, room temperature
For the Vanilla Buttercream Frosting
1½ cups unsalted butter, softened
4–5 cups powdered sugar, sifted
2–3 tablespoons heavy cream or whole milk
1 tablespoon pure vanilla extract
Pinch of salt
Optional Garnishes
Rainbow sprinkles
Fresh berries
White chocolate curls
Piped buttercream rosettes
Instructions
Prepare the Cake Pans
Preheat your oven to 350°F (175°C). Grease two 8-inch round cake pans, line the bottoms with parchment paper, and lightly grease the parchment to ensure easy release after baking.
Mix the Dry Ingredients
In a medium bowl, whisk together the all-purpose flour, baking powder, and salt until well combined. Set aside while preparing the wet ingredients.
Cream the Butter and Sugar
In a large mixing bowl, beat the softened butter and granulated sugar using a stand mixer or hand mixer on medium-high speed for 3–5 minutes, until the mixture becomes pale, light, and fluffy. This step creates the tender, bakery-style crumb.
Add the Eggs and Vanilla
Add the eggs one at a time, beating well after each addition and scraping down the sides of the bowl as needed. Mix in the vanilla extract until fully incorporated.
Combine the Batter
Reduce the mixer speed to low. Add one-third of the flour mixture, followed by half of the milk. Continue alternating the flour mixture and milk, beginning and ending with the flour.
Gently fold the sour cream into the batter until completely smooth. Be careful not to overmix, as this helps keep the cake soft and tender.
Bake the Cakes
Divide the batter evenly between the prepared cake pans and smooth the tops with an offset spatula.
Bake for 28–35 minutes, or until the tops are lightly golden and a toothpick inserted into the center comes out clean or with a few moist crumbs.
Remove the cakes from the oven and allow them to cool in the pans for 10–15 minutes before turning them out onto a wire rack to cool completely.
Prepare the Vanilla Buttercream
In a large bowl, beat the softened butter for 3–4 minutes until creamy and fluffy.
Gradually add the powdered sugar, one cup at a time, beating well after each addition. Add the vanilla extract, salt, and heavy cream, then continue beating for another 3–5 minutes until the frosting becomes light, smooth, and airy.
If needed, add a little more cream for a softer frosting or additional powdered sugar for a firmer consistency.
Assemble the Cake
Place one cake layer onto a serving plate or cake board.
Spread a generous layer of vanilla buttercream evenly over the top.
Position the second cake layer on top and gently press it into place.
Apply a thin crumb coat over the entire cake and refrigerate for 15–20 minutes to lock in any loose crumbs.
Finish by frosting the top and sides with the remaining buttercream, smoothing it with an offset spatula or cake scraper for a classic bakery-style appearance.
Decorate
Pipe decorative borders around the edges using any remaining frosting.
Add sprinkles, fresh berries, white chocolate curls, or your favorite decorations for a beautiful finishing touch.
Chill and Serve
Refrigerate the cake for 20–30 minutes before slicing for cleaner, neater pieces.
Allow the cake to sit at room temperature for 15–20 minutes before serving for the softest texture and richest flavor.
Description
Costco-Style Vanilla Cake is a rich, buttery celebration cake featuring soft vanilla layers and fluffy buttercream frosting. The combination of butter, sour cream, and whole milk creates an incredibly moist crumb, while the smooth vanilla buttercream delivers the signature bakery-style finish everyone loves.
Perfect for birthdays, weddings, holidays, family gatherings, and special occasions, this homemade version captures the classic taste and texture of a wholesale bakery favorite while using simple pantry ingredients.
Pro Tips for Best Results
Use room-temperature ingredients for a smooth, evenly mixed batter.
Cream the butter and sugar thoroughly to achieve a light and fluffy cake.
Do not overmix once the flour is added to keep the cake tender.
Use a kitchen scale to divide the batter evenly between the pans.
Chill the crumb-coated cake before applying the final layer of frosting for a smooth, professional finish.
Variations
Fill the cake with fresh strawberries or raspberry preserves between the layers.
Add white chocolate chips to the batter for extra richness.
Flavor the buttercream with almond extract for a bakery-inspired twist.
Decorate with colorful sprinkles for birthdays or elegant piping for weddings.
Use the batter to make cupcakes, reducing the baking time to 18–22 minutes.
Nutritional Information
Prep Time: 30 minutes
Bake Time: 30 minutes
Cooling Time: 1 hour
Total Time: 2 hours
Servings: 12–16 slices
Approximate per serving:
Calories: 620 kcal
Protein: 6 g
Carbohydrates: 72 g
Fat: 34 g
Conclusion
Costco-Style Vanilla Cake is the ultimate homemade bakery cake with tender vanilla layers, silky buttercream frosting, and rich flavor in every bite. Beautiful enough for celebrations and simple enough for family gatherings, this classic cake delivers the soft texture, creamy frosting, and elegant presentation that make it a timeless favorite.