Lemon Layer Cake

This lemon cake is three layers of lemon cake filled lemon curd and Swiss Meringue Buttercream.

Course Dessert

Servings 12 servings

Preheat Oven: Preheat oven to 350°F (175°C). Spray cake pans with cooking spray and line the bottoms with parchment paper.
Prepare Dry Ingredients: In a medium bowl, mix together cake flour, baking powder, baking soda, and salt. Set aside.
Prepare Wet Ingredients: In a small bowl, mix together milk and yogurt. Set aside.
Cream Butter and Sugar: In the bowl of a stand mixer, cream together butter and lemon sugar until fluffy and pale in color.
Add Eggs and Extracts: Add eggs to the mixer one at a time, mixing well after each addition. Stir in vanilla and lemon extracts.
Combine Dry and Wet Ingredients: Add 1/3 of the flour mixture to the mixer and mix until well combined. Then pour in 1/2 of the yogurt mixture and mix. Repeat the process, ending with the remaining flour mixture. Stir in the lemon juice.
Prepare for Baking: Evenly divide the batter among the prepared pans (about 2 cups of batter per pan). If you only have two cake pans, bake two layers and set aside the remaining batter until you have a cool pan to bake the last layer.
Bake: Bake for 20 minutes or until a cake tester comes out clean when inserted into the middle. The top should also spring back when gently pressed with a finger. Cool in the pan for 10 minutes, then transfer to a wire rack to cool completely.

Prepare Double Boiler: Place a large pot with a couple inches of water on the stove and bring to a simmer. Ensure the mixer bowl fits tightly in the pot without touching the bottom.
Heat Egg Whites: In the mixer bowl, combine egg whites, sugar, and salt. Whisk to combine. Place the mixer bowl over the simmering water and cook until it reaches 161°F (72°C) or is no longer grainy, whisking consistently. This should take about 4-5 minutes. If you don’t have an instant thermometer, carefully place your finger or a spoon in the hot mixture. If you can feel any sugar grains, it’s not ready.
Whisk Egg Whites: Remove from heat and whisk in a stand mixer on high until the bowl is no longer hot and stiff peaks have formed, about 10-15 minutes. If it’s very hot or humid, this may take longer. You can place the bowl and whisk in the fridge for 10 minutes if needed.
Add Butter: Slowly add butter to the stiff peaks with the mixer running on high. Wait until the butter is fully incorporated before adding more. Continue mixing until all the butter is added and the buttercream is smooth and silky. If the buttercream looks curdled, refer to the my detailed recipe for SMBC..
Flavor and Color: Add salt, flavorings, and color as desired.

Layer and Frost: Place one cake layer on a cake board. Spread 1/2 cup of lemon curd over the top, leaving a 1/2-inch border. Pipe a circle of buttercream around the lemon curd, then spread 1/2 cup of frosting over the top. Repeat with the second layer.
Crumb Coat: For the top layer, spread a thin layer of buttercream over the top and sides. Chill the cake for at least 30 minutes to set the crumb coat.
Final Frosting: Frost and decorate the cake with the remaining buttercream.
Serve: Serve the cake at room temperature. Remove from the fridge about an hour

For more detailed instructions on making SMBC, refer to my post on SMBC.
The frosted and filled cake should be kept in the fridge. It tastes best at room temperature, so remove it from the fridge about an hour before eating.
The frosted and filled cake will keep in the fridge for about 5 days.
Unfrosted cake layers can be kept at room temperature tightly wrapped for up to 2 days or frozen for up to 3 months.