American Flag Cake

American flag cake made as a patriotic sheet cake: two white cake layers baked in a 12x18 pan, then frosted and topped with a blueberry canton and strawberry red stripes. Finished with clean white stripes (piped frosting or banana) for an Independence Day cake look.

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Prep Time 45

Cook Time 35

Cooling 1

Total Time 2 20

Servings: 20 servings

Course: Dessert

Cuisine: American

Calories: 520

Ingredients Equipment Method Notes

Ingredients

White cake base

2 box white cake mix Use the ingredients listed on the box (eggs, oil, and water).

Frosting

2 cup unsalted butter Softened to room temperature.
6 cup powdered sugar
2 tsp vanilla extract
6 tbsp heavy cream Start with 4 tbsp and add up to 6 tbsp for spreadable texture.

Flag decorations

2 cup fresh blueberries Keep dry so they set into the canton cleanly.
2 lb fresh strawberries Hulled and sliced lengthwise into flat strips.
1 banana slices Optional: use for the white stripes instead of extra frosting.

Equipment

1 sheet pan

Method

Bake the sheet cake

Bake both cake mixes in a large 12x18 sheet pan (or two 9x13 pans joined together) according to package directions. Cool completely after baking.

Make the white buttercream

Beat the softened unsalted butter until fluffy, about 2-3 minutes. Gradually add powdered sugar, then beat in vanilla extract and heavy cream until smooth and spreadable.

Frost the cake

Spread a thick, even layer of white buttercream over the entire top of the cooled sheet cake. Use gentle pressure to level the surface for sharp stripes.

Decorate the American flag

In the upper left corner, arrange the fresh blueberries into a dense rectangle for the blueberry canton. Press lightly so the fruit sits flat and stays vivid.

Add the red stripes

Create red stripes by arranging rows of sliced fresh strawberries flat across the length of the cake. Keep the rows uniform in height for a clean flag pattern.

Add the white stripes

Fill the white stripes by piping extra frosting in rows between the strawberry rows, or by placing thin banana slices. Keep the white stripes straight from edge to edge.

Chill and serve

Refrigerate the decorated cake until ready to serve, at 35°F (2-4°C), to set the buttercream and fruit. Slice into squares.

Notes

For the sharpest-looking flag, chill the frosted cake 30 minutes before arranging the fruit so the buttercream firms up. Refrigerate leftovers in a covered container up to 3 days; freezing is not recommended because the strawberries and bananas soften after thawing. If you want a lighter option, swap 1 cup of the powdered sugar with an equal amount of powdered sugar substitute labeled for frosting and adjust heavy cream as needed for the same spreadable texture.