This Lemon White Chocolate Cake is a bright and elegant dessert that combines tangy lemon flavor with creamy white chocolate. Moist layers of lemon cake are filled with a luscious white chocolate ganache and topped with a smooth lemon-infused frosting. Perfect for celebrations or a special treat, this cake is sure to impress.

Ingredients

2 cups all-purpose flour (250g)
2 teaspoons baking powder
½ teaspoon kosher salt
¾ cup unsalted butter, room temperature (170g)
1 ¼ cups granulated sugar (250g)
2 tablespoons lemon zest (about 2 lemons, hold 1 teaspoon aside for the frosting)
2 tablespoons vegetable or canola oil (30mL)
3 large eggs, room temperature
1 teaspoon pure vanilla extract
2 tablespoons lemon juice (30mL, about one lemon)
⅔ cup buttermilk, room temperature (160mL)
4 ounces white chocolate chips* (114g, roughly ¾ cup)
2 ounces heavy cream** (60mL)
1 teaspoon pure vanilla extract
4 ounces white chocolate*, melted and cooled to room temperature (114g)
1 cup unsalted butter, room temperature (226g)
2 cups confectioners’ sugar (240g)
3 tablespoons heavy whipping cream (45mL)
1 teaspoon lemon zest
½ teaspoon pure vanilla extract

Instructions

Step 1: Preheat your oven to 350°F. Prepare two 8-inch cake pans by buttering them, lining with parchment paper, then buttering the parchment paper as well to ensure easy cake removal. Prepare lemon zest and juice.
Step 2: Sift together the flour, baking powder, and kosher salt. Set aside.
Step 3: In a stand mixer fitted with the paddle attachment, cream the butter, sugar, and lemon zest from 2 lemons (reserve 1 teaspoon for frosting) on medium-high speed until light and fluffy, about 3-4 minutes. Scrape down the bowl once.
Step 4: With the mixer on low, drizzle in the oil, then increase speed to medium-high and mix for 1-2 minutes. Add eggs one at a time, mixing after each addition. Add vanilla extract with the last egg and beat for 1-2 minutes. Scrape the bowl as needed.
Step 5: Stir lemon juice into the buttermilk.
Step 6: On low speed, alternately add the flour mixture and buttermilk mixture in thirds—start with one-third flour, then half the buttermilk, another third flour, remaining buttermilk, and last third flour. Stop and scrape the bowl when flour is still visible. Finish mixing gently with a spatula; do not overmix.
Step 7: Divide batter evenly between the prepared pans (about 500g each). Bake for 22-30 minutes, until a toothpick inserted in the center comes out with a few moist crumbs.
Step 8: Cool cakes in pans for 15 minutes, then transfer to a wire rack to cool completely before frosting.
Step 9: To prepare the white chocolate ganache, place white chocolate chips in a bowl. Heat heavy cream until hot and bubbling at edges (do not boil). Pour over chocolate and let sit for 2 minutes, then stir until smooth. Add vanilla and continue stirring until fully combined. Let cool until thick and spreadable.
Step 10: Melt the 4 ounces white chocolate for the frosting using a double boiler or microwave. Cool to room temperature.
Step 11: In a mixer, beat butter on high for 5 minutes, scraping halfway through. Add confectioners’ sugar and mix on low until incorporated. Add heavy cream and beat on high for 5 more minutes. Scrape down, then add melted white chocolate, lemon zest, vanilla, and a pinch of salt. Beat 2 minutes more until smooth and fluffy.
Step 12: Assemble the cake once layers are completely cool. Level cakes if needed by slicing off the dome tops. Place one cake layer topside up on your serving surface. Spread about 2 tablespoons of frosting to hold it in place. Pipe a frosting dam around the edges and fill the center with the white chocolate ganache. Smooth the ganache and place the second cake layer topside down over it.
Step 13: Apply a thin crumb coat of frosting over the entire cake to create a semi-naked look. Use remaining frosting to pipe decorative rosettes or buttons if desired.

Tips & Variations

Use high-quality white chocolate for the ganache and frosting to ensure a smooth, rich flavor.
Allow cakes to cool completely before frosting to prevent melting and sliding.
If you prefer a fully frosted cake, simply double the frosting recipe.
For extra lemon flavor, add a teaspoon of lemon extract to the frosting along with the zest.

Storage

Store the cake covered in the refrigerator for up to 4 days. Bring to room temperature before serving for best flavor and texture. If frozen, wrap tightly and freeze for up to 2 months; thaw overnight in the refrigerator before serving.

How to Serve

Serve this delicious recipe with your favorite sides.

FAQs

Can I use regular milk instead of buttermilk?

Yes, you can substitute regular milk mixed with a tablespoon of lemon juice or vinegar to mimic buttermilk’s acidity and help the cake rise properly.

How do I prevent the white chocolate from seizing when melting?

Use gentle heat either via a double boiler or short bursts in the microwave, stirring frequently. Avoid water contact and overheating, as moisture causes white chocolate to seize and become grainy.