No patriotic party is complete without a 4th of July Flag Cake. Every summer, I host a BBQ party on the 4th of July. This American flag cake is served for dessert, but it’s the show-stopper every year. It’s a soft, fluffy vanilla sheet cake topped with creamy buttercream and decorated with fresh berries to resemble the American flag. It’s light, moist, and beautifully balanced with sweetness and freshness in every bite.

This flag cake recipe is always a huge hit at Memorial Day, Independence Day gatherings and all the summer parties that follow. It’s patriotic without being fussy, once the buttercream is spread, you simply build the design right on the top of the cake with fresh fruit.
If you’ve never made a festive cake before, you might be nervous. But let me tell you that the recipe is less intimidating than it seems. It looks stunning on the table, but the process is surprisingly easy. Yes, it takes some time coming together, but no complicated steps are involved. You don’t need advanced decorating skills or equipment, just fresh strawberries, blueberries, and a little creativity to bring this 4th of July flag cake to life. If you’re looking for a foolproof celebration dessert, this flag sheet cake recipe is exactly what you need.
This Patriotic flag cake with berries pairs perfectly with a few of my warm-weather favorites, try Pineapple Chicken Kabobs for an easy backyard main, then add a quick rice option like Chicken and Shrimp Fried Rice for feeding a crowd. For a simple weeknight-style dinner that still feels summery, Orange Chicken and Rice is another reader favorite to keep in your seasonal rotation.
[feast_advanced_jump_to]
Why You Will Love This American Flag Cake
Festive & Eye-Catching — The vibrant berries create a beautiful red white and blue flag cake that looks festive, pretty and delicious. It becomes the centre of the gathering, as if the party is thrown for this cake!
Soft & Fluffy Texture — From sponge to the topping, the texture is light and fluffy. The base is made with a soft vanilla sheet, giving you a light and moist crumb that pairs perfectly with the creamy buttercream frosting. Storebought cake mix cannot replace that!
Easy to Decorate — You don’t need piping skills or fancy tools like pastry bag, star nozzle. This flag cake comes together with simple layering and fresh fruit.
Perfect for a Crowd — This 4th of July sheet cake serves 12 to 20 people, making it ideal for BBQs, patriotic parties, and family gatherings.
Ingredients and Substitutions

For the Vanilla Cake
- All-Purpose Flour & Cornstarch: All purpose flour makes the base. Cornstarch helps mimic a cake flour texture. This combination creates a soft, tender crumb for your cake.
- Baking Powder & Baking Soda: Both are important for a light, fluffy texture and a rise in this Flag sheet cake.
- Salt: A little goes a long way. It balances sweetness and enhances flavor. Use any salt you have.
- Unsalted butter & Oil: Butter adds flavor, while oil keeps the cake moist. Don’t skip either if you want the perfect vanilla sheet cake with buttercream. You can use any butter, dairy or dairy-free.
- Sugar: Sweetens and helps create that soft texture.
- Eggs: They bind everything, provide structure, and add richness.
- Vanilla Extract: Vanilla adds warmth and flavour. You can use vanilla bean paste as a substitute.
- Lemon Juice: Lemon juice brightens the flavor slightly. You can use fresh lemon juice or store bought.
- Buttermilk: Keeps the cake soft and tender. You can substitute with milk and 1 teaspoon vinegar. Or else substitute with sour cream.
For the Buttercream
- Butter: Use softened butter for a smooth, creamy frosting. Dairy or dairy-free both will work fine.
- Powdered Sugar: It sweetens and thickens the buttercream. You can use powdered coconut sugar as a substitute.
- Vanilla Extract: Enhances the flavor of the frosting. Vanilla essence or vanilla bean paste can be used as a substitute.
- Heavy Cream: Adjusts the consistency to make it fluffy and spreadable.
Decorating the Flag
- Fresh Blueberries & Fresh Strawberries: They create a stunning patriotic flag cake with berries, while adding natural sweetness and freshness. Don’t skip them.
See recipe card for quantities.
Instructions (How To Make 4th Of July Flag Cake)
Preheat the oven to 350°F (175°C). Grease and line a 9x13-inch pan with parchment paper. (optional)

In a bowl, whisk together flour, cornstarch, baking powder, baking soda, and salt.

In a separate large bowl, beat butter and sugar for 2–3 minutes until light and fluffy on a medium speed.

Add the eggs one at a time, beating well after each addition.

Mix in the oil, vanilla, lemon juice, ½ cup of buttermilk until combined.

Add the flour mixture in 3 parts, alternating with buttermilk (begin and end with dry). Mix just until combined, don’t overmix.

Pour batter into the prepared pan and smooth the top. Bake 22–28 minutes, or until a toothpick inserted in the center comes out clean.

For Vanilla Buttercream Frosting, beat the sugar and butter for 3-4 minutes. Mix in Vanilla.

Add heavy cream 1 tablespoon at a time until the frosting is fluffy and spreadable.

Spread buttercream evenly over the cooled cake.

In the top-left corner, create a “blue square” with fresh blueberries.
Press blueberries into the corner for the “stars,” then line up rows of strawberries to create the red stripes, leaving the frosting to show through as the white stripes. Chill 20–30 minutes to set, then slice and serve.
Hint: Decorate the cake right before serving (or within 1–2 hours) so the strawberries stay bright and don’t bleed into the frosting.

Variations For 4th of July Flag Cake
- Chocolate Flag Cake — Swap the vanilla base with a chocolate cake for a twist. The berries still stand out beautifully against the darker base of this American Flag Cake.
- Cream Cheese Frosting Flag Cake — Replace buttercream with 12 ounces of cream cheese and ¼ cup greek yogurt for a lighter version of this 4th of July cake. It feels fresher and less sweet, especially in summer.
- Berry-Filled Flag Sheet Cake — Add a layer of whipped cream and fresh berries inside the cake before frosting. This makes your patriotic flag cake with berries even more flavorful and juicy.
Serving Suggestions
Summer BBQs: This American Flag Cake pairs perfectly with grilled dishes. You can serve it as dessert after Pineapple Chicken Kabobs, Oven Roasted Chicken, Air Fryer BBQ Chicken Thighs, or Baked Lemon Pepper Thighs.
Dessert Table: Serve alongside fruits and other desserts like Orange Poppy Seed Muffins, Puff Pastry Hearts with Raspberries, Nutella Puff Pastry, Lemon Mini Bundt Cakes, or Chocolate Covered Strawberries.
With Ice Cream: A scoop of vanilla ice cream complements this vanilla sheet cake with buttercream beautifully.

Equipment
- 9x13-inch baking pan
- Parchment paper or nonstick spray
- Mixing bowls
- Hand mixer or stand mixer
- Measuring cups and spoons
- Rubber spatula
- Whisk or Offset spatula or butter knife (for frosting)
- Cooling rack
- Serrated knife (for clean slices)
Storage And Make-Ahead Tips
Make Ahead: You can bake the cake a day in advance and decorate before serving.
Refrigerator: Store the leftover cake in an airtight container in the fridge for up to 3–4 days.
Freezer: You can freeze the unfrosted cake for up to 2 months. Thaw and decorate later.

Top Tips For The Best 4th of July Cake
- Don’t overmix the batter to keep the cake soft and tender.
- Use room temperature ingredients for even mixing.
- Let the cake cool completely before frosting.
- Pat berries dry before decorating to prevent bleeding. Place them on the cake right before serving otherwise they will get soggy.
- Chill briefly before slicing for clean cuts.
FAQ
Yes! Bake the cake a day ahead and decorate before serving for best freshness.
The combination of butter, oil, and buttermilk keeps it moist and fluffy.
Yes, for a lighter version of this 4th of July Flag Cake, whipped cream works well.
Make sure berries are dry before placing them on your red white and blue flag cake.

Related
Looking for other recipes like this? Try these:
Pairing
These are my favorite dishes to serve with this Red white and blue flag cake recipe:
If you tried this 4th of July Flag Cake recipe or any other recipe from my blog, I’d love to hear your thoughts! ⭐ Please leave a STAR rating and share your experience in the COMMENTS below. Your support means so much and helps me continue creating delicious recipes. Thank you for being part of this journey!

4th of July Flag Cake (Easy American Flag Sheet Cake)
Equipment
- Measuring cups and spoons
- Mixing Bowls
- Sheet Pan
- Spatula
- Cooling rack
- Hand Mixer or Stand Mixer
Ingredients
Fluffy Vanilla Sheet Cake
- 2 ¼ cups all-purpose flour
- ¼ cup cornstarch
- 1 teaspoon baking powder
- ½ teaspoon baking soda
- ½ teaspoon salt
- ½ cup unsalted butter softened
- 1 ½ cups sugar
- ¼ cup neutral oil canola/vegetable
- 3 large eggs room temperature
- 2 teaspoons vanilla extract
- 1 tablespoon lemon juice
- 1 cup buttermilk room temperature
Vanilla Buttercream Frosting
- 1 cup unsalted butter softened (2 sticks)
- 2 ½ cups powdered sugar
- 2 teaspoon vanilla extract
- 1 –4 tablespoons heavy cream add as needed for texture
Flag Decoration
- Fresh blueberries about 2 cups
- Sliced strawberries about 3 cups
Instructions
Bake the cake
- Preheat oven to 350°F (175°C). Grease and line a 9x13-inch pan with parchment paper.
- In a bowl, whisk together flour, cornstarch, baking powder, baking soda, and salt.
- In a large bowl, beat butter and sugar for 2–3 minutes until light and fluffy.
- Mix in the oil.
- Add the eggs one at a time, beating well after each. Mix in vanilla and lemon juice.
- Add the dry ingredients in 3 additions, alternating with buttermilk (start and end with dry). Mix just until combined—don’t overmix.
- Pour batter into the pan and smooth the top.
- Bake 22–28 minutes, or until a toothpick inserted in the center comes out clean.
- Cool in the pan for 15 minutes, then cool completely before frosting.
Make the buttercream
- Beat the butter for 2 minutes until smooth and creamy.
- Add powdered sugar gradually, mixing on low at first, then increasing speed.
- Mix in vanilla.
- Add heavy cream 1 tablespoon at a time until the frosting is fluffy and easy to spread.
Decorate like an American flag
- Spread buttercream evenly over the cooled cake.
- Make a “blue square” in the top-left corner using blueberries.
- Add rows of sliced strawberries to create red stripes, leaving white frosting between them for the white stripes.
- Chill 20–30 minutes to set, then slice and serve.
Notes
- Measure flour correctly: Spoon and level the flour so the cake stays fluffy (too much flour can make it dense).
- Don’t overmix: Mix just until combined after adding the dry ingredients for a tender crumb.
- Cool completely before frosting: Warm cake will melt the buttercream and make it slide.
- Buttercream texture: Add heavy cream slowly—stop when it’s fluffy and spreadable (not runny).
- Decorate close to serving: Add berries within 1–2 hours of serving to prevent juices from bleeding into the frosting.
- Dry the fruit: Pat strawberries and blueberries dry before decorating so the top stays neat.
- Clean slices: Chill the cake 20–30 minutes, then cut with a sharp knife wiped clean between slice































































































































































































































































































































































































































































































































































































































