American Flag Cake
Add some patriotic flare to your baking this Fourth of July. An American flag cake is easy to make from scratch and has the most delicious fresh berries on top. The dessert is guaranteed to be a hit this summer.
Cake decorating is easy when all you have to add is add berries on top! No special frosting tool needed, just some fresh blueberries and raspberries to make the stars and stripes, respectively. I love this cake not only for its red, white and blue decoration, but also for its tender texture and strong vanilla flavor. This is a dessert any American would be proud to bake!
Why You’ll Love This Recipe
- Patriotic theme. Whether it’s the Fourth of July or Memorial Day, this cake will fit the occasion.
- Fresh summer berries. Using fruit while it’s in season is the best way to adorn a dessert!
- Tried-and-true recipe. This is my vanilla sheet cake recipe, which was tested several times to get the right vanilla flavor and tender texture. I also used my go-to buttercream frosting recipe.
- Party food. This is the perfect dessert to bring to backyard barbecues. It serves a crowd!
Ingredient Notes
- Butter: Use unsalted butter that is room temperature for both the cake and the frosting. Different brands of salted butter have varying amounts of salt added so it’s best to measure it separately.
- Sour cream: For an moist cake, use full-fat sour cream that is room temperature. Plain yogurt is a good substitution.
- Milk: Use whole milk for a moist texture and rich flavor. In a pinch, low-fat milk can be used.
- Vegetable oil: For a fluffy texture, use vegetable oil or canola oil (any flavorless oil works).
- Vanilla extract: This is the primary flavor for the cake so be sure to use a good quality 100% pure vanilla (not imitation). I prefer Watkins or Rodelle.
- Baking powder and soda: These leavening agents help the cake rise in the oven. Check that they are fresh and not expired.
- Confectioners’ sugar: Also known as powdered sugar, this is used to make the buttercream frosting.
- Berries: Use fresh berries that are in season for the best flavor. Rinse and dry completely before suing.
Refer to the recipe card for full list of ingredients and measurements.
Recipe Variations
Substitute the berries. Sliced strawberries make good “stripes” for the flag cake. You can also try blackberries for the star portion.
Use a different frosting. Cream cheese frosting also tastes delicious. Beat 1 cup block-style cream cheese with 1/4 cup unsalted butter. Add 1 cup confectioners’ sugar and 2 teaspoons vanilla extract. Mix until smooth. Another option is Swiss meringue buttercream, which I use on my triple berry layer cake.
How to Make an American Flag Cake
- Whisk together the dry ingredients—flour, baking powder, baking soda and salt. Set aside.
- Beat butter and sugar until creamy. Mix in the eggs one at a time.
- Add the vegetable oil, sour cream and vanilla. Mix just until combined.
- Alternate adding the flour and milk, beginning and ending with the milk.
- Transfer batter to a 9×13 metal baking pan and bake at 350 F for 35 minutes. Cool completely.
- For the frosting, beat butter until smooth and creamy. Mix in the confectioner’s sugar and a pinch of salt. Add the vanilla and milk. then mix until smooth.
- Frost cooled cake. In the top left corner, outline a square with blueberries. Fill the in the square with more blueberries.
- Use raspberries to create a line at the top and bottom of the cake. Add more lines of berries for the “stripes”.
Expert Tips
Do not over-mix when adding the flour and milk. You want to mix just until combined otherwise the cake will turn out dense. Also remember to scrape down the sides and bottom of the bowl as necessary for even mixing.
Let the cake cool completely before frosting. If the cake is still warm, the frosting will melt and the berries may slide off!
Make sure the berries are dry. Rinse your berries after buying them, but make sure there is no water on them before putting them on the cake. If they are wet, their juices will bleed and the flag won’t be as clean.
Use room temperature ingredients. Not only are they easier to combine, but they also create a better texture within the batter. As a result, the cake has a more tender texture.
Weigh the ingredients with a scale. This is the best way to measure flour. If you don’t have a scale, spoon the flour into a measuring cup and level with a knife (don’t pack it down).
Make Ahead and Storage Tips
Make ahead the frosting and store covered in the refrigerator for up to 1 week. Let it sit at room temperature and give it a few good stirs before frosting the cake. The cake batter cannot be made ahead of time. The baking powder and baking soda start to lose their effectiveness once in contact with wet ingredients.
Store cake covered in the refrigerator for up to 3 days. The berries may leak some juices into the frosting, but it will still taste delicious.
Freeze cake for up to 3 months. Flash freeze for one hour or until firm, then wrap individual slices in plastic wrap and store in an airtight container in the freezer. Defrost in the refrigerator before bringing to room temperature.
Recipe FAQ
There are plenty of methods to prevent domed cakes. Some bakers say bake at a lower temperature for a longer time, others swear by baking strips. Personally, I just use a serrated knife to level the cake before frosting.
This recipe is a adaptation of my vanilla cupcake recipe. There are some slight changes needed to make cupcakes so I suggest you follow that recipe for best results.
Related Recipes
Check out these other recipes perfect for the Fourth of July.
Did you love this recipe? Please leave a 5-star 🌟🌟🌟🌟🌟 rating in the recipe card below and if you REALLY loved it, consider leaving a comment further down the page.
Get the Recipe: American Flag Cake
Ingredients
Vanilla Sheet Cake
- 2 ¾ cups (325 g) cake flour
- 1 teaspoon baking powder
- ½ teaspoon baking soda
- ½ teaspoon salt
- 1 ½ cup (300 g) granulated sugar
- ½ cup (113 g or 1 stick) unsalted butter, room temperature
- 4 large eggs, room temperature
- ½ cup (120 ml) vegetable oil
- ⅓ cup (75 g) full-fat sour cream (or plain yogurt), room temperature
- 1 ½ tablespoons pure vanilla extract
- 1 cup (240 ml) whole milk, room temperature
Buttercream Frosting
- 1 cup (226 g or 2 sticks) unsalted butter, room temperature
- 2 ½ cups (300 g) confectioners' sugar, sifted
- Pinch of salt
- 2 teaspoons pure vanilla extract
- 1-2 tablespoons milk
- 1 pint (2 cups) blueberries
- 1 ½ pints (3 cups) raspberries
Instructions
Cake
- Preheat oven to 350° F. Grease a 9×13 baking pan or line with parchment paper and set aside.
- In a medium bowl, whisk together cake flour, baking powder, baking soda and salt. Set aside.
- In a large mixing bowl, cream together the butter and sugar until light and fluffy, about 5 minutes. Add the eggs one at a time, beating well after each addition. Beat in the vanilla extract, sour cream and vegetable oil. It’s okay if the batter looks a little curdled. Scrape down the bottom and sides of the bowl as necessary.
- Gradually add in the flour mixture in three parts, alternating with milk (So it goes flour, milk, flour, milk, flour). Mix until batter is uniform and smooth.
- Transfer the batter to prepared pan and spread evenly. Bake at 350 F for 30 to 35 minutes. The cake is down when a toothpick inserted in the center comes out with little to no crumbs. Place pan on a wire rack and allow cake to cool completely before frosting, about 2 hours.
Frosting
- For the frosting, beat butter until light and fluffy, about 3 minutes. Add confectioners’ sugar and salt, then mix until medium speed until combined. add vanilla and 1 Tablespoon milk. Mix just until combined. Scrape down the bottom and sides of the bowl as necessary. If a thinner frosting consistency is desired, add another tablespoon of milk.
Assembly
- Use an offset spatula to spread buttercream frosting into an even layer on top of the cake.
- In the top left corner, outline a square with blueberries. Fill it in with more blueberries for your “stars”.
- Next, arrange a line of raspberries on the top and the bottom of the cake. Add remaining lines of raspberries, spacing them apart for the red and white “stripes”. Slice and serve.
