American Flag Red Velvet Sheet Cake

1 day ago 6

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This American Flag Red Velvet Sheet Cake is soft, rich, and topped with cream cheese frosting and fresh berries for an easy patriotic dessert.

A slice of Red Velvet Sheet Cake topped with cream cheese frosting, fresh strawberries, raspberries, and blueberries sits on a white plate with a gold fork—an inviting patriotic dessert perfect for any celebration.

Know Before You Scroll

Servings: 12 slices

Prep: 25 minutes

Cook: 40 minutes

Total Time: 1 hour 5 minutes

flour, cocoa powder, buttermilk, butter, oil, cream cheese, berries

Light cocoa, buttery, tangy cream cheese, fresh berries.

9×13-inch pan, mixing bowls, whisk, hand or stand mixer, offset spatula.

Don’t skip chilling before slicing — it makes clean, bakery-style cuts.

Bake and frost the cake a day ahead, then decorate just before serving for the freshest look.

Use store-bought frosting if you need a shortcut.

A rectangular Red Velvet Sheet Cake topped with white frosting and fresh strawberries, with a slice removed. Blurred plates of assorted berries are visible in the background, making this a perfect patriotic dessert for any celebration.

In The Test Kitchen

I wanted this cake to feel just as good as it looks, because flag cakes can sometimes be all decoration and no payoff. This one fixes that. The crumb is soft and velvety with just enough cocoa for depth, while the combination of butter and oil keeps it rich but still light.

The whipped cream cheese frosting was the real game changer. Instead of something dense and overly sweet, it’s fluffy, slightly tangy, and spreads like a dream. Once I tested the berry layout a few times, I found that keeping the pattern simple made it look cleaner and made the cake much easier to assemble.

Ingredient Notes

A variety of baking ingredients arranged on a white surface—perfect for creating a Red Velvet Sheet Cake—with eggs, butter, flour, sugar, milk, cream, cocoa powder, vanilla, salt, strawberries, and a bottle of oil.

Granulated sugar keeps the crumb soft and moist, all-purpose flour gives standard structure, cocoa powder adds subtle red velvet depth, buttermilk adds tang and tenderness, butter and oil balance flavor and moisture, vinegar helps with lift, and red food coloring gel gives the bold signature color.

No specific substitutions were noted in the source doc for the cake base; use the listed ingredients for the intended texture and color.

Full-fat cream cheese gives the best stability, softened unsalted butter keeps the frosting smooth, confectioners’ sugar sweetens and thickens, and heavy cream lightens it into a whipped texture.

No specific frosting substitutions were noted in the source doc. For a shortcut, the doc does note that store-bought frosting can be used in the post.

Fresh blueberries work best for the stars section, strawberries give bright red stripes, and raspberries add texture and a deeper red contrast.

The source doc suggests you can swap the berries for sliced cherries or red currants while keeping the red-white-blue look.

Fresh berries section of the produce aisle.

Detailed instructions with photos for each step below.

Step By Step Instructions

Make the batter

Whisk together the sugar, flour, cocoa powder, baking powder, baking soda, and salt. In another bowl, whisk the eggs, 1½ cups buttermilk, melted butter, oil, vinegar, vanilla, and red food coloring until smooth. Combine the wet and dry ingredients until you have a silky, lump-free batter.

mixing dry ingredients, whisking them together, blending in wet ingredients to form pink batter, and mixing until the batter is smooth and red.

Bake the cake

Pour the batter into a lined 9×13-inch pan and spread it evenly to the corners. Bake at 350°F until the top looks set and a toothpick comes out clean. Let it cool completely in the pan — the surface should feel soft but spring back when lightly pressed.

an empty parchment-lined pan, a pan filled with red cake batter, and a pan with the baked red velvet sheet cake ready to become a festive patriotic dessert.

Whip the frosting

Beat the butter until pale and fluffy, then add the cream cheese and mix until smooth. Add vanilla and salt, then gradually mix in the confectioners’ sugar. Pour in the heavy cream and whip until light, airy, and spreadable.

creaming butter and sugar, adding dry ingredients, and blending until smooth with electric beaters in glass bowls.

Frost the cake

If the cake has a slight dome, gently level it for a flat surface. Spread about two-thirds of the frosting over the cake, smoothing it into an even layer with an offset spatula.

A metal spatula spreads creamy white frosting over a Red Velvet Sheet Cake in a rectangular baking pan.

Create the flag design

In the top-left corner, place blueberries in tight rows to form the stars section. Add rows of halved strawberries for the stripes, then double rows of raspberries for contrast. Pipe or spread thin lines of frosting between the rows to mimic white stripes.

Four-step collage showing the creation of an American Flag Cake—a patriotic dessert with blueberries for the blue section, strawberries and raspberries for red stripes, and piped white frosting for stars and white stripes.

Chill and slice

Refrigerate the cake for 30 to 60 minutes until the frosting firms up. When sliced, you’ll get clean edges and defined layers that hold their shape.

A close-up of a Patriotic Dessert, this Red Velvet Sheet Cake slice is topped with creamy white frosting and fresh raspberries. The moist cake boasts a vibrant red color and is being lifted on a spatula.

Prep Time: 25 minutes

Cook Time: 40 minutes

Chill Time: 30 minutes

Total Time: 1 hour 5 minutes

Serves 12 slices

For the Cake

▢ 1¾ cups granulated sugar
▢ 3 cups all-purpose flour
▢ 3 tablespoons cocoa powder
▢ 1½ teaspoons baking powder
▢ ½ teaspoon baking soda
▢ 1 teaspoon salt
▢ 2 large eggs
▢ 1½ cups buttermilk (at room temperature)
▢ 10 tablespoons unsalted butter (melted)
▢ ¾ cup vegetable oil
▢ 1 teaspoon vinegar (white or apple cider)
▢ 2 teaspoons vanilla extract
▢ 1 tablespoon red food coloring gel

For the Cream Cheese Whipped Buttercream

▢ 1 cup unsalted butter (2 sticks, softened)
▢ 8 ounces cream cheese (softened)
▢ 4 cups confectioners’ sugar (plus more as needed)
▢ ⅓ cup heavy cream (plus a little more if needed)
▢ 2 teaspoons pure vanilla extract
▢ Pinch of salt

For Decoration

▢ Fresh blueberries
▢ Fresh strawberries (halved)
▢ Fresh raspberries

Preheat the oven to 350°F (177°C). Grease and line a 9×13-inch pan with parchment paper. In a large bowl, whisk together the sugar, flour, cocoa, baking powder, baking soda, and salt. In another bowl, whisk the eggs, buttermilk, melted butter, oil, vinegar, vanilla, and red food coloring until combined. Pour the wet ingredients into the dry ingredients and whisk until smooth. Spread the batter evenly in the pan and bake for 35–40 minutes, or until a toothpick inserted in the center comes out clean. Let the cake cool completely.
In a large bowl, beat the butter on medium-high until fluffy (about 2 minutes). Add the cream cheese and beat until smooth. Mix in the vanilla and salt. Gradually add confectioners’ sugar, one cup at a time, beating well after each addition. Add the heavy cream and whip on high for 2–3 minutes until light and fluffy. Adjust consistency with a touch more sugar or cream as needed.
Spread about two-thirds of the frosting evenly over the cooled cake using an offset spatula. Smooth the surface to create a clean base layer. Reserve the remaining one-third for piping and details.
In the top-left corner, arrange whole blueberries in neat rows to form the stars section. For the stripes, alternate rows of halved strawberries and double rows of raspberries with swirls of white frosting between each red stripe. Use the remaining frosting to fill in any open spaces around the blueberry section.
Refrigerate the finished cake for 30–60 minutes to help the frosting set, then slice and serve. The cake can be made a day ahead — just cover and chill until ready to serve.

Erren’s Top Tips

Use room temperature ingredients for a smoother batter and better rise.
Don’t overmix once the batter comes together.
Dry the berries well before placing them.
Use an offset spatula for a smooth finish.
Chill before slicing for clean squares.

Variations & Add-Ins

Swap the berries with sliced cherries or red currants for a different look.
Add an extra tablespoon of cocoa powder for a deeper chocolate flavor.
Turn the recipe into cupcakes and decorate each with a mini flag design.

Storage & Freezing

Store covered in the refrigerator for up to 3 days.
Let slices sit at room temperature for about 15 minutes before serving.
Freeze the unfrosted cake for up to 2 months and thaw overnight before decorating.