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+ servings

Flag Cake (From Scratch)

An iconic 4th of July dessert, this time made 100% from scratch!
Course Dessert
Cuisine American
Prep 1 hour
Cook 30 minutes
Total 1 hour 30 minutes
Servings 18 to 24 servings
Calories 799 kcal
Author Michelle


For the Cake:

  • 3 cups all-purpose flour
  • cup cornstarch
  • 1 teaspoon baking soda
  • 1 teaspoon kosher salt
  • 1 cup + 2 tablespoons unsalted butter at room temperature
  • 3 cups granulated sugar
  • 6 extra-large eggs at room temperature
  • 1 cup sour cream at room temperature
  • teaspoons vanilla extract

For the Frosting:

  • 2 cups unsalted butter at room temperature
  • 24 ounces cream cheese at room temperature
  • 4 cups powdered sugar
  • teaspoons vanilla extract

For the Decorating:

  • 24 ounces raspberries
  • 16 ounces blueberries


  1. Make the Cake: Preheat oven to 350 degrees F. Grease and flour a 13x18-inch half sheet pan; set aside.
  2. In a medium bowl, whisk together the flour, cornstarch, baking soda and salt; set aside.
  3. Cream together the butter and sugar on medium-high speed until light and fluffy, about 3 minutes. Reduce the mixer speed to medium and add the eggs, two at a time, beating well after each addition and scraping down the sides of the bowl between additions.
  4. Reduce the mixer speed to low and add the sour cream and vanilla extract, mixing until just combined. Give the batter a stir with a rubber spatula.
  5. Keeping the mixer on low speed, gradually add the dry ingredients, mixing until the ingredients are just combined. Fold the batter with a rubber spatula to ensure all of the flour has been incorporated.
  6. Pour the batter into the prepared pan and spread into an even layer. Bake until golden brown and a thin knife inserted into the center comes out clean, 20 to 30 minutes. Place the pan on a wire rack and cool completely before decorating.
  7. Make the Frosting: Cream together the butter and cream cheese on medium-high speed until completely smooth, about 3 minutes. Reduce the mixer speed to medium-low and gradually add the powdered sugar. Once all of the sugar has been added and is incorporated, add the vanilla extract and increase the mixer speed to medium and beat until completely combined, about 1 minute.
  8. Decorate the Cake: Take about three-quarters of the frosting and spread in an even layer over the top of the cake. Using a toothpick, lightly draw a square in the upper lefthand corner of the cake. Fill in the square with blueberries. Place two rows of raspberries across the top of the cake to make a red stripe. Place the rest of the frosting into a decorating bag with a large tip and pipe two rows of frosting below the raspberries. Continue alternating rows of raspberries and frosting until you get to the bottom of the cake. Pipe stars onto the blueberries in whatever design you'd like.
  9. The cake can be kept at room temperature if it's cool and air conditioned; otherwise leftovers should be stored in the refrigerator, covered in plastic wrap. The cake will keep for up to 3 days, but is best served within a day of making and decorating it.

Recipe Notes

Nutritional values are based on one serving

Nutrition Facts
Flag Cake (From Scratch)
Amount Per Serving
Calories 799 Calories from Fat 432
% Daily Value*
Fat 48g74%
Saturated Fat 28g175%
Cholesterol 184mg61%
Sodium 348mg15%
Potassium 198mg6%
Carbohydrates 88g29%
Fiber 3g13%
Sugar 65g72%
Protein 7g14%
Vitamin A 1640IU33%
Vitamin C 12.5mg15%
Calcium 82mg8%
Iron 1.8mg10%
* Percent Daily Values are based on a 2000 calorie diet.