Flag Cake

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This healthy Flag Cake is a fun, patriotic treat to make for a holiday weekend. It’s naturally dairy-free & gluten-free, and there are tons of options below to help you customize it to your needs.

oat flour flag cake topped with berries

This cake is the result of some experimenting I’ve done this week. I wanted to see if I could turn my vegan cream cheese into a vegan cream cheese frosting, and I’ve also been testing a new oat flour cake recipe.

Why not combine them and turn them into a dessert for the Fourth of July? This also works for Memorial Day, Labor Day, or you can even make it into a Canadian Flag, using only strawberries, for Canada Day.

Why You’ll Love It

  • It’s gluten-free. Made with oat flour, this cake is naturally gluten-free, but do be sure to make sure the flour you’re using is “certified gluten-free” to make sure there’s no contamination during processing.
  • It’s dairy-free. This cake uses coconut oil instead of butter in the batter, and is frosted with coconut whipped cream. (Or use my vegan cream cheese frosting.)
  • It’s naturally sweetened. The cake is naturally sweetened with coconut sugar, which has a slightly lower glycemic index compared to white sugar. Feel free to use any other granulated sugar that you have on hand, though!
  • It feeds a crowd. You’ll get 15 large slices from this cake, or more if you prefer to slice on the smaller side.
  • It’s easy to decorate. No artificial food dyes are required to make this red, white, and blue cake. Just slice some strawberries, and have a cup of blueberries ready to go.
  • You can make it ahead. Bake the cake the night before, and keep it in the fridge tightly covered overnight. You can frost and add the berries shortly before serving. (The berries can start to sweat into the white frosting if you prepare this too far in advance, FYI.)

toppings added to flag cake

Keep in mind, this flag cake is more of a general idea, rather than a recipe that you have to follow 100% accurately. If you don’t want to make an oat flour cake, you can also try my Paleo Banana Cake, Vanilla Almond Flour Cake, Chocolate Almond Flour Cake, or Coconut Flour Cake.

Need a vegan recipe? Try these toppings on my Vegan Chocolate Cake, which is naturally grain-free and gluten-free.

Note: If you’re using a recipe that only makes one 8-inch cake, you’ll need to double the ingredients to fill a 9-by-13-inch pan. I’ve found that the baking time also needs to increase from 30 minutes to closer to 45 minutes when baking a cake this size, but be sure to keep an eye on the cake after the 35-minute mark, just to be sure.

How to Make It

  • Stir. Start by whisking together the dry ingredients to break up any clumps, then add in the wet ingredients and mix until smooth.
  • Bake. Pour the batter into a greased 9-by-13-inch pan (or a similar rectangle pan for a flag shape) and bake until a toothpick comes out clean after being inserted in the center. This takes about 45 minutes.
  • Cool. Let the cake cool completely, so the toppings won’t melt! I like to place mine in the fridge, so the cake will be cold when I frost it.
  • Decorate! Top with coconut whipped cream, or your favorite frosting, then add on the blueberries and sliced strawberries. I usually can squeeze in about 4 rows of strawberry “stripes” so it won’t be a perfect American flag, but I think you get the idea.

finished flag cake by bowl of berries

Frosting Ideas

The cake pictured in this post is topped with an experimental vegan cream cheese frosting, using my most recent vegan cream cheese recipe. My family requested a more traditional frosting, made with real powdered sugar, but I wanted to keep it dairy-free for those in my family who have a dairy intolerance.

This recipe isn’t 100% perfect in the photos, because I used too much cream cheese and it melted! So, here’s what I’d suggest if you want to try it at home:

  • 1/2 cup vegan cream cheese, at room temperature
  • 3 to 4 cups organic powdered sugar
  • 1/2 teaspoon vanilla extract

Stir the ingredients together in a large bowl, starting with just 1 cup of powdered sugar at a time, until it’s as thick as you’d like. This is not the type of frosting that can be “piped” or that will set. It remains relatively runny, so just keep that in mind. My family didn’t care, since it tastes so good!

Try my Vegan Cream Cheese Frosting made with sweet potatoes, or Coconut Whipped Cream for an easy white frosting that is naturally sweetened with only maple syrup.

oat flour flag cake topped with berries
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5 from 2 votes

Flag Cake

This patriotic cake is baked in a rectangular pan for a "flag shape" and then topped with fresh berries to look like an American Flag! It's perfect for Fourth of July, Memorial Day, or any summer party.
Course Dessert
Cuisine gluten-free
Keyword flag cake, healthy
Prep Time 20 minutes
Cook Time 45 minutes
Total Time 1 hour 5 minutes
Servings 15
Calories 399kcal


  • 3 cups oat flour (400 grams)
  • 2 1/4 cups coconut sugar (367 grams)
  • 4 large eggs (200 grams)
  • 3/4 cup melted coconut oil (158 grams)
  • 1 1/2 teaspoons baking soda (9 grams)
  • 3/4 teaspoons salt (6 grams)
  • 2 tablespoons vanilla extract (17 grams)
  • 1 1/2 cups water


  • 2 heaping cups Coconut Whipped Cream (or 2 cups of your favorite frosting)
  • 1 pound sliced strawberries
  • 1 cup fresh blueberries


  • Preheat the oven to 350ºF and grease a 9-by-13-inch pan well. In a large bowl, combine the flour, sugar, baking soda, and salt, and whisk well, until there are no visible clumps.
    dry ingredients mixed together
  • Add in the eggs, oil, water, and vanilla, and stir again, until the batter looks smooth. Pour it into the prepared pan and bake for 40 to 45 minutes, or until a toothpick comes out clean when inserted in the center.
    wet ingredients mixed and added to pan
  • Let the cake cool completely before frosting. I like to place it in the fridge to cool, so the cake will be chilled when I frost it. Top the cake with coconut whipped cream or your favorite frosting (see recipe ideas in the post above), then top with sliced strawberries and blueberries to make an American Flag look, with the blueberries in the top left corner, and the strawberries making red "stripes."
    frosting and toppings added to cake
  • Serve this cake chilled, soon after adding the fruit. The sliced strawberries may start to sweat into the frosting if they sit for too long at room temperature. Store any leftovers in an airtight container in the fridge for up to 3 days. If you're planning to make this cake ahead of time, don't add the fruit until just before serving.
    finished flag cake with slice removed


Nutrition information is for 1 of 15 slices, using full-fat coconut milk as the whipped topping. This will vary based on what type of frosting (and how much) you use. This is automatically calculated, and is just an estimate, not a guarantee.


Calories: 399kcal | Carbohydrates: 42g | Protein: 6g | Fat: 24g | Saturated Fat: 19g | Polyunsaturated Fat: 1g | Monounsaturated Fat: 2g | Cholesterol: 50mg | Sodium: 301mg | Potassium: 262mg | Fiber: 2g | Sugar: 19g | Vitamin A: 78IU | Vitamin C: 19mg | Calcium: 34mg | Iron: 3mg

If you try this Flag Cake, please leave a comment below letting me know how you like it. And if you make any modifications, I’d love to hear about those, too.

Reader Feedback: What’s your favorite treat to make for Fourth of July?

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Debra P.

Hey, Megan: I have written you and didn’t get an answer. Therefore, I’m sending this to you now in the Comments section, as you’ve instructed. Thanks for your recipes – they’re delicious!!

I know you were trying out different air fryers and I was wondering if you would mind telling me what brand/size/wattage air fryer you use??

I would love to start air frying, but I’m really torn as to which one to buy (which one is really the best or easier to use)??

I get confused with the wattages of the different brands when dealing with different recipes and wattages. You know where the recipes calls for the dish to be air fried at 1100 wattage for so many minutes; yet, if I already have an air fryer which is 1500 wattage, how do I adjust? If the wattage doesn’t matter, then I air fry my dish at a lower amount of minutes?? Still, how do I adjust……some are the same, but there are some that are different!

I’ve looked at them in the store and some look way too small (even though it’s just my husband and myself and sometimes my 9 yo grandson). I really like the ones with shelves….it looks like you could air fry more…… maybe a couple of foods at the same time.

Don ‘t mean to bug you…..I really don’t know who to ask….I’m a diabetic II so I think the air fryer will definitely help with the foods I should eat.

Thanks so much for your response – I know you are so busy with family and all, I really do appreciate it!!


Hey 🙂 could I replace the eggs with flax eggs? Or chia seeds?

    Megan Gilmore

    My guess is that a starch will work better, like arrowroot or potato starch. Oat flour gets “gummy” really fast, so flax or chia eggs usually add to that problem. But feel free to experiment with it!

Lauren Rodgers

Can’t wait to make this! Question: What kind of baking pan is pictured? Thanks so much!


I love that you’re working on more oat flour cake recipes! Made this one yesterday for my daughter’s 2nd birthday party, and she loved it! I used your 2-ingredient chocolate ganache on top, and it was perfect.


i do love this recipe a lot.One question:
i am looking for a recipe for almond wiped cream
i can not have: aquafaba, coconut cream or butter and refine sugar.Any tip?
thank you


This cake was absolutely delicious!! My son is on a health protocol and can’t have processed sugar but coconut sugar is allowed so I decided to give this a shot and it was 10/10! New fave cake recipe!


You know what I feel this is missing .. and maybe it’s just me. But … like. To turn this into a poke cake. Where you poke it with the handle of a wooden spoon and pour something like a strawberry syrup all over it or something. Mot your thing don’t worry about it. But I like to leave ideas when I think about it. I like to think it helps you think of ideas. Which I can only assume can be a challenge after so many years.

    Megan Gilmore

    I’ve never had a poke cake before, but that sounds like fun! Let me know if you experiment with it. 🙂


Can I use milk instead of water in this recipe?

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