American Flag Sheet Cake

The Fourth of July is almost here, and what shows our pride just as much – perhaps even more than – Roman candles and firecrackers? The quintessential American flag cake, that’s what!

American Flag Sheet Cake - With easy vegan option. Moist chocolate sheet cake smothered in vanilla buttercream and decorated with berries. A crowd-pleaser that is as cute as it is delicious!

We’ve all seen these cakes, right? A staple of Independence Day barbecues everywhere, these cakes feature white frosting with rows of strawberries forming the stripes and blueberries in a square in the upper left.

Right around this time of year, every year, I have a jonesing to make a red, white, and blue dessert. One of these fancy-schmancy flag cakes is always one of the first things to come to mind, though I never quite get around to it. Because lazy. But this year, I was determined to make it happen.

American Flag Sheet Cake - With easy vegan option. Moist chocolate sheet cake smothered in vanilla buttercream and decorated with berries. A crowd-pleaser that is as cute as it is delicious!

But because I don’t eat dairy, I wanted to make a version that could easily be made vegan. So I started with a wacky cake base. Wacky cake is that classic depression-era chocolate cake that’s already vegan because it’s made without milk and eggs. (We actually grew up calling it crazy cake, and it was my very favorite dessert. Yummmm … just warm-out-of-the-oven square of crazy cake with a generous dollop of Cool Whip … okay, I’m back.)

When you make this cake, you start with flour, baking soda, cocoa powder, and sugar. Then, make indentations in the dry ingredients and add vinegar, oil, vanilla, and water.

American Flag Sheet Cake - With easy vegan option. Moist chocolate sheet cake smothered in vanilla buttercream and decorated with berries. A crowd-pleaser that is as cute as it is delicious!

Then you stir!

This cake is totally fun to make with the kiddos. And their Barbies.

American Flag Sheet Cake - With easy vegan option. Moist chocolate sheet cake smothered in vanilla buttercream and decorated with berries. A crowd-pleaser that is as cute as it is delicious!

I wanted this cake to be big so there would be room for all those strawberry stripes. So I spread a big ol’ batch of wacky cake batter into a large rimmed baking pan and baked it all up, Texas sheet cake style.

American Flag Sheet Cake - With easy vegan option. Moist chocolate sheet cake smothered in vanilla buttercream and decorated with berries. A crowd-pleaser that is as cute as it is delicious!

After it cools, we’ve got that buttercream (seen in a big giant pile up there).

This is where the vegan substitution comes in, if you like – just swap out the butter for Earth Balance sticks, use plant-based milk, adjust the powdered sugar if needed, and there you go. A vegan American flag cake! Because vegans should get to eat flag cake too.

After spreading out and smoothing that glorious layer of buttercream (this one was made with Earth Balance and looks incredible, right? It is!)

Anyway, after smoothing out the buttercream, I like to mark the upper third of the cake. This is where the blueberries will go; strawberry stripes, all around that.

American Flag Sheet Cake - With easy vegan option. Moist chocolate sheet cake smothered in vanilla buttercream and decorated with berries. A crowd-pleaser that is as cute as it is delicious!

I also like to use my offset spatula to draw “stripe” lines in the cake (bonus: this also helps to smooth out any errors or strawberry-row adjustments you had to make along the way). But the lines are totally optional.

American Flag Sheet Cake - With easy vegan option. Moist chocolate sheet cake smothered in vanilla buttercream and decorated with berries. A crowd-pleaser that is as cute as it is delicious!

Because it’s made in a shallow sheet pan, this makes a cute, thin little cake. I love it this way – more area on the top means more berries. And the berries + the vanilla buttercream + the moist chocolate cake = deee-eee-eeee-llllicious.

American Flag Sheet Cake - With easy vegan option. Moist chocolate sheet cake smothered in vanilla buttercream and decorated with berries. A crowd-pleaser that is as cute as it is delicious!

I wasn’t quite sure what to name this thing, by the way. I wanted to pay homage to the wacky cake base, and I was really tempted to call this a Wacky American Flag Cake. We Americans can own our personal wackiness as well as our wacky cake, right? As I was discussing the name with my guy, our 5-year-old piped in.

“Hey, I know what to call it!”

“What?”

“A blertren!”

American Flag Sheet Cake it was. A bit boring, but less potentially offensive – and a bit more descriptive than “blertren.”

Happy Fourth of July!

Oh, and thank you to my gal for her assistance making the cake and thanks to my guy for being willing to model it. 🙂

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American Flag Sheet Cake

Moist chocolate sheet cake smothered in vanilla buttercream and decorated with berries. This festive flag cake is as cute as it is delicious. The cake itself is already vegan; the buttercream can easily be made vegan too!

Ingredients:

Chocolate wacky cake base:

  • 2 cups all-purpose flour
  • 1 1/2 cups granulated sugar
  • 1/2 cup cocoa powder
  • 1 1/2 teaspoons baking soda
  • 1 teaspoon fine-grain sea salt or table salt
  • 2 teaspoons pure vanilla extract
  • 2 tablespoons white vinegar or cider vinegar
  • 1/2 cup vegetable oil or melted coconut oil
  • 1 1/2 cups water

Vanilla buttercream:

  • 2 sticks (1 cup) unsalted butter or Earth Balance buttery sticks, room temperature
  • 4 cups powdered sugar
  • 1 teaspoon pure vanilla extract
  • 2 tablespoons milk

Berry topping:

  • 6 ounces (about 1 cup or 1/2 pint) fresh blueberries, washed and dried
  • 32 ounces (about 6 cups, 2 pounds, or 2 1/2 pints) fresh strawberries, washed, hulled, halved, and patted dry

Directions:

  1. Preheat oven to 350 degrees Fahrenheit. Grease a 13″ x 18″ rimmed baking sheet – spray with your favorite non-stick spray or wipe down with a bit of oil.
  2. In a large bowl, sift together the flour, sugar, cocoa powder, baking soda, and salt. Stir with a whisk or a wooden spoon to combine.
  3. Using the back of a wooden spoon, make three indents in the flour mixture. Into one indent, pour the vanilla. Into the second, pour the vinegar. Into the third, add the oil. Pour the water over the top. Stir well until combined.
  4. Spread the batter in the baking sheet and, using an offset spatula, spread the batter to the edges of the pan, making it as level as possible. Bake for 14-17 minutes; until the sides have pulled away from the edge a bit and a toothpick inserted into the center comes out clean. Pull the cake out of the oven and set on a wire rack to cool completely.
  5. While the cake cools, make the buttercream frosting. Using a stand mixer or hand mixer, whip the butter until smooth. Add a cup of powdered sugar and mix in at low speed. Add remaining powdered sugar, a cup at a time, and mix until smooth. Add the vanilla and the milk. Mix until smooth and an easily spreadable consistency. If too thick, add more milk – just a teaspoon at a time, as it thins out easily. If too thin, add more powdered sugar.
  6. Once the cake is completely cool, frost it with the buttercream – simply smooth it all over the top in a thin, even layer.
  7. Now, it’s time to decorate! Visually divide the cake into thirds and, in the top third, fill in with rows of blueberries. Add rows of halved strawberries next; the amount of stripes depends on the size of your strawberries, so just eyeball it, and if you need to adjust the berries, you can use the tip of the offset spatula or the tip of a spoon to create stripes in between the rows of berries.
  8. Serve as soon as possible; it can be made ahead of time, but the strawberries will probably start to leak after awhile, so keep that in mind.

Make ahead: You can bake the sheet cake ahead of time (just cover with plastic wrap and keep at room temp until you’re ready to frost). I recommend frosting and adding the berries as close to serving time as possible. The sugar in the frosting brings out some of the juices in the berries, so if it sits for awhile, the strawberries start leaking a bit.

Vegan/dairy-free option:

The cake recipe is already vegan; to make the frosting vegan, use Earth Balance for the butter and almond or soy milk instead of dairy milk.

All images and text © for Kitchen Treaty.

Karen Raye

Kare is a vegetarian home cook living among carnivores. She loves creating irresistible and flexible recipes that help multi-vore families like hers keep the peace - deliciously.