American Flag Cake

American flag cake with a thick white buttercream layer and a crisp blueberry canton with strawberry red stripes. This patriotic sheet cake uses two baked white layers and fresh fruit rows for a vivid red-white-blue flag design.

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Prep Time 45

Cook Time 35

cooling 1

Total Time 2 20

Servings: 20 servings

Course: Dessert

Cuisine: American

Ingredients Equipment Method Notes

Ingredients

White cake layers (use box directions)

2 boxes white cake mix Use the eggs, oil, and water/milk called for on the box (collectively).

Buttercream frosting

2 cups unsalted butter Softened.
6 cups powdered sugar
2 tsp vanilla extract
4 tbsp heavy cream Add 4–6 tbsp as needed for spreadable consistency.

Flag decoration

2 cups fresh blueberries Rinse and pat dry.
2 lb fresh strawberries Hulled and sliced lengthwise.
1 banana slices Optional for white stripes; use in addition to extra white frosting if preferred.
1 extra white frosting Optional backup for white stripes, as needed.

Equipment

1 sheet pan

Method

Bake the cake

Bake both white cake mixes in a large 12x18 sheet pan or two 9x13 pans joined together according to package directions. Bake until a toothpick comes out clean, then cool completely.

Make the white buttercream

Beat the softened unsalted butter until fluffy at medium speed. Gradually add the powdered sugar, then mix in the vanilla extract and heavy cream until smooth and spreadable, adjusting with more cream if needed.

Frost the cake

Frost the entire top of the cooled sheet cake with a thick, even layer of white buttercream. Use an offset spatula or the back of a spoon to keep the surface level for clean fruit lines.

Decorate the American flag

In the upper left corner, arrange the fresh blueberries into a dense rectangle to form the canton. Press them in lightly so the corner stays crisp.

Add the red stripes

Create red stripes by arranging the sliced fresh strawberries flat across the length of the cake. Keep the rows uniform so the stripes read clearly from overhead.

Fill the white stripes

Fill the white stripes by piping extra white frosting in rows between the strawberry rows or by placing thin banana slices. Aim for straight, even lines across the whole surface.

Chill and serve

Refrigerate until ready to serve. Slice into squares right before serving so the fruit looks fresh and the frosting holds its shape.

Notes

Pro tip: for the cleanest “flag” look, slice strawberries lengthwise to the same thickness and dry the fruit well before decorating. Refrigerate covered up to 3 days; freezer not recommended. Dietary swap: for a lighter option, replace 1/2 of the frosting’s butter with plant-based butter sticks (choose one that creams well) while keeping powdered sugar proportions the same.