Made in one bowl, this American flag sheet cake comes together in no time. Buttermilk and oil make it especially moist, and the whipped cream cheese frosting is the perfect complement.

A just-baked flag cake.

I have a hard time not making pastry-crusted and biscuit-topped bubbling berry desserts for occasions such as the Fourth of July, but earlier this week, a flag cake materialized, and I don’t think my children will allow the holiday to pass from here on out without one.

I have wanted to make Deb Perelman’s flag cake ever since she posted it ten years ago, and while I do regret not making it sooner, in some ways the timing was perfect. I had found myself with only one kid home, and I had told her she would “just have to entertain herself for the day.”

But when I saw her slump onto the couch, letting out a sigh of exhaustion after giving a somewhat good go at playing alone — riding once around the block on her bike, playing fetch with Pepe, writing a letter to her cousin Arabella — I asked: Should we make a flag cake?

She lept off the couch and squealed: Really?!

Yes, really. This was such a fun and simple baking project. Wren, who is 9 years old, weighed and mixed the batter with minimal supervision and decorated the entire cake herself. I helped with the frosting mostly because my Kitchen Aid is on its last legs and requires a forceful whack to kick the engine into gear.

The recipe, which is the same as this one-bowl buttermilk birthday cake recipe, is below, and I can’t recommend it enough — the cake comes together in no time, the frosting is heavenly, and the berry-flag motif is oh so festive.

Friends, I’m wishing you all a Happy Fourth 🇺🇸🇺🇸🇺🇸🇺🇸

American Flag Sheet Cake, Step by Step

Gather your ingredients:

Ingredients to make flag cake on a countertop.

Whisk together the dry ingredients…

Dry ingredients to make a flag cake.
The dry ingredients whisked together for a flag cake.

… then add the wet ingredients.

The wet ingredients added to the dry ingredients for a flag cake.

Stir until smooth.

Just-mixed flag cake batter in a large bowl.

Pour the batter into a buttered and parchment-lined 9×13-inch pan. I’m using this USA Pan, which I love:

Flag cake batter added to a 9x13-inch cake pan.

It will feel like not enough batter, but I promise…

A 9x13-inch pan filled with cake batter.

… it will bake up beautifully:

A just-baked cake in a 9x13-inch pan.

Spread the whipped cream cheese frosting over the top:

A baked cake with topped with whipped cream-cream cheese frosting.
A frosted flag cake.

Then begin your assembly. You’ll need to dust half of the raspberries and blueberries with powdered sugar:

Sifting powdered sugar over a plate of raspberries.
Finishing up the flag cake.

Present your cake proudly, perhaps with a pup by your side.

Wren, holding a flag cake, aside Pepe.
A just-baked flag cake.

Cut and serve.

A slice of flag cake.

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A just-baked flag cake.

Easy American Flag Sheet Cake

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Inspired by Deb Perelman’s flag cake. I’ve used my one-bowl buttermilk birthday cake recipe as the base and my favorite whipped cream cheese frosting, but I’ve used Deb’s assembly method.


for the cake:

  • 1 1/2 cups (192 g) all-purpose flour
  • ¼ teaspoon salt
  • ½ teaspoon baking soda
  • 1 1/2 teaspoons baking powder
  • ½ cup (115 g) neutral oil, such as grapeseed or avocado
  • 1 cup (215 g) sugar
  • 2 eggs, lightly beaten
  • ½ cup + 2 tablespoons (158 g) buttermilk
  • 2 teaspoons vanilla extract
  • 1 recipe Whipped Cream Cheese Frosting

for decorating:

  • 3 to 4 cups raspberries
  • 1 cup blueberries
  • confectioners sugar


  1. Preheat the oven to 350ºF. Whisk together the flour, salt, baking soda, baking powder, and sugar. Add the oil, eggs, buttermilk, and vanilla, and stir to combine.
  2. Coat a 9×13-inch pan with nonstick spray (or butter liberally). Line with parchment paper. Pour the batter into each pan and bake for 25 to 30 minutes or until an inserted toothpick comes out clean. Cool in pan completely.
  3. To assemble: Spread the frosting over the cooled cake. Place half of the blueberries on a large plate. Sift confectioners sugar over the top. Place 1.5 cups of the raspberries on a large plate or small sheet pan. Sift confectioners sugar over the top. Start by making the blueberry-star section. Then make the stripes by lining the bottom edge of the pan with red raspberries (as in not confectioners sugar-dusted). Make a row of confectioners sugar-dusted raspberries and repeat until the stripes are complete.
  • Prep Time: 30 minutes
  • Cook Time: 25 minutes
  • Category: Dessert
  • Method: Oven
  • Cuisine: American