Lemon Chiffon Berry Flag Cake
June 28 2020
What could be more patriotic than making a flag cake? Especially one this pretty and this delicious? This light, lemon chiffon cake is made in a sheet pan, ideal for serving to a crowd this Fourth of July. It's then topped with a beautiful silky vanilla Swiss meringue buttercream. Decorate the cake with raspberries, blueberries and lemon meringue kisses and stars. While it takes a bit of effort, it is sure to delight! As a shortcut, you can always use store-bought vanilla meringue cookies in place of the kisses and make the stars out of the buttercream. Either way, you'll have a gorgeous, delicious cake for the holiday. Happy Independence Day, America!
Berry Flag Cake
Makes: 1 sheet cake
Total Time: 1 hour
Lemon Meringue Kisses & Stars (recipe here) or see Chef's Note below
Lemon Chiffon Cake:
1/2 lb (2 sticks) unsalted butter, room temperature, plus extra to butter the sheet pan
3 cups cake flour (See Chef's Note below)
2 tsp baking powder
1 1/2 tsp baking soda
1 tsp salt
5 large eggs, at room temperature
2 cups sugar
1 tsp pure vanilla extract
2 tbsp lemon zest
2 tbsp lemon juice
1 cup buttermilk, well shaken (see Chef's Note below)
3 packages (6 ounces each or 1 1/3 cups each) packages Driscoll's Raspberries
1 package (6 ounces or 1 1/4 cups) package Driscoll's Blueberries
For the Vanilla Swiss Buttercream:
6 fresh large egg whites, at room temperature
1 1/2 cups sugar
2 cups confectioners sugar
1/8 tsp kosher salt
3/4 cup solid vegetable shortening, at room temperature
1 lb (4 sticks) unsalted butter, at room temperature
1 tsp pure vanilla extract
Make the lemon chiffon cake:
Preheat oven to 350°F. Butter 12" x 18" sheet pan, don't forget to get in the corners. In a large mixing bowl sift together cake flour (see substitute below), baking powder and baking soda. Mix in salt and set aside.
Separate eggs and put yolks aside in a small bowl. In the bowl of an electric stand mixer fitted with whisk attachment, beat egg whites until you reach stiff peaks. Transfer egg whites into a separate bowl.
Change mixer to paddle attachment. In a clean bowl cream together butter and sugar until pale yellow. Start mixer at low speed and gradually set on high speed for about 1 to 2 minutes. Add vanilla, lemon zest, lemon juice and buttermilk; mix until combined and add egg yolks one at a time until fully incorporated.
Add flour mixture in 2 to 3 batches while mixer is on low speed. Scrape side and bottom of bowl as necessary. Do not overbeat. Turn off mixer and gently fold in egg whites with a large rubber spatula until just barely incorporated; keep as much air in the batter as possible.
Spread batter evenly in the sheet pan. Smooth it out using an off-set spatula. Bake until lightly golden brown, approximately 30 to 35 minutes. Test for doneness by inserting toothpick in center of cake, it should come out clean. Set on rack and cool completely, preferably 3 to 4 hours, minimum 1 hour.
Make the Vanilla Swiss Buttercream:
In a large metal bowl whisk together sugar and egg whites. Set bowl over a pot of boiling water as a double boiler, constantly whisk until the sugar has completely dissolved.
Pour mixture in bowl of electric stand mixer fitted with whisk attachment and whip on high speed until it is thick, shiny and white. The peaks should be very firm. If they are not firm, the frosting will not be as stable.
While the egg whites are whipping, sift confectioners sugar. After you reach stiff peaks, add confections sugar and salt all at once into mixer on very low speed until it is fully incorporated.
Quickly add butter and shortening in 2 to 3 additions. Add vanilla extract.
Switch to paddle attachment and beat on high speed until smooth, approximately 5 minutes. The longer you beat the frosting, the whiter the color will become.
Note: The buttercream can be stored at room temperature for 4 days, up to 2 weeks in refrigerator, 2 months in the freezer.
Assemble the Flag Cake:
Add frosting to center of cake and spread evenly using an off set spatula. Start with half the frosting to determine if you want a light or heavy layer of frosting.
Starting with the bottom edge of the cake, begin placing 2 rows of raspberries along the bottom edge of the cake. Place a single row of meringue kisses and alternate with double row of raspberries. Top row should end with a double row of raspberries.
Leave room for the blueberry section. Place 10 blueberries across the top left corner and 8 blueberries down vertically. This should be the equivalent of the height of the top 3 rows of raspberries and meringue kisses; horizontally it will match 4 meringue kisses across. If you can make it even, this will just make it easier to cut the cake for serving.
Finish the cake with little meringue stars. Place a small amount of frosting on the backside of the meringue star and place on top of the blueberry section, the frosting will act as a glue. As an alternative, the stars can be made out of frosting using a Wilton 1M tip.
Cake flour substitute: 1 cup cake flour = 2 tbsp cornstarch into 1 cup measuring cup and fill with all-purpose flour, make sure to level flour.
Buttermilk substitute: Add 1 tbsp lemon juice or white vinegar into a liquid measuring cup; add enough milk till it reaches 1 cup. Stir and let it sit for 5 minutes. It will thicken and look curdled.
To save time, you can purchase store-bought vanilla meringue cookies. These can substitute for the meringue kisses. Make stars out of frosting by using a small star tip or the Wilton 1M tip.
If you make the cake in advance, wrap it tightly with plastic after the cake has completely cooled. Fruit can be assembled in advance but suggest to place them on the same day as serving to eliminate the need to refrigerate the entire sheet cake. If you want the meringues to stay crisp and chewy, place them on the cake just before serving as they can begin to absorb moisture from the frosting.
Recipe from Judy Kim NYC