Lemon sheet cake is a bright and fresh citrusy cake that is perfect for spring and summer celebrations. Tender lemon cake is made with fresh lemon zest and juice, topped with a silky cream cheese frosting. This cake can be made in three different pan sizes - 13x18, 9x13, and as a 9-inch two layer cake!
Preheat oven to 350 degrees Fahrenheit. Generously grease a 9x13 or 13x18 inch baking pan and set aside. Or, grease and flour two 9-inch round cake pans and set aside.
In a large bowl, add room temperature butter and granulated sugar. Beat until creamed and fluffy. Add vanilla extract, lemon zest, and eggs, one at a time, mixing until incorporated and smooth.
In a separate bowl, sift together dry ingredients: cake flour, baking powder, and salt. In a liquid measuring cup, add lemon juice to milk.
Add half of the dry ingredients to your butter mixture. Mix until just combined. Add half of the milk mixture, again mixing until just combined. Repeat once more to add remaining dry ingredients and milk until just combined.
Pour batter into prepared baking sheet (or evenly between two round cake pans) and spread into an even layer.
9x13 baking pan: 30-34 minutes13x18 half sheet pan: 17-19 minutesTwo 9 inch round cake pans: 24-27 minutesTwo 8 inch round cake pans: 26-30 minutesBake your cake for the time listed above, or until cake is baked through in the center and a toothpick comes out clean. Ovens can run hot, so I suggest checking your cake for doneness 5 minutes early.
Remove cake from oven and allow to cool completely in the pan(s) on a wire cooling rack.
Cream cheese frosting
*As written, frosting will cover a 9x13 cake, 13x18 cake, or the top and sides of a 2-layer cake. To use frosting as a filling, make an additional half batch of frosting.
In a large bowl, add room temperature cream cheese and butter and beat with a hand mixer (or stand mixer) until creamy, about 1 minute.
Add vanilla extract and salt and mix until incorporated.
Add confectioner's sugar, half at a time, and mix on low speed until sugar is incorporated. Switch to high speed and beat until light and fluffy, about 2 minutes.
For a sheet cake: Spread frosting in an even layer onto cooled cake. Optionally, add sprinkles or lemon zest as a garnish before frosting crusts.
Layer cake assembly (optional)
Gently flip and remove cakes from their pans. Trim the rounded tops with a serrated knife to make flat layers. Place one layer, cut side down, onto a cake stand or plate.
Using a pastry bag or a plastic bag with the corner snipped, pipe a small amount of frosting around the top perimeter of the cake. This will prevent the lemon curd from seeping out of the edges. Fill the center with lemon curd and spread into an even layer. Place other cake layer, cut side down, on top.
Frost the top and sides of your layer cake with prepared frosting. Slice and serve!
Sheet cake can be sliced to serve up to 24 guests.
Baking is an exact science. I do not recommend substituting any ingredients. The butter, milk, eggs, and sugar keep your cake moist - substituting any of these ingredients with a lower fat alternative can change the texture and make your cake dry.
Frosted cake will keep in a sealed container at room temperature for 2 hours, in the refrigerator for 2-3 days, or frozen for up to 2 months. If refrigerating or freezing unfrosted cake layers, wrap tightly in plastic and place in a tightly sealed container. Thaw overnight in the refrigerator, then bring to room temperature for an hour before serving.
Cream cheese frosting needs to be refrigerated if it sits out for longer than 2 hours. Store frosted baked goods in the refrigerator in a tightly sealed container. Remove and bring to room temperature 1 hour before serving.