This Flag Sheet Cake will set off fireworks on your tastebuds! A moist vanilla cake tinted  to match each flags colours, patriotic sprinkles inside and a buttercream designed American flag on one side and a Canadian flag on the other. This is the perfect festive cake for both Canada Day and Fourth of July! 

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Queenslee Appétit Turns TWO!

It’s officially the 2 YEAR ANNIVERSARY for Queenslee Appétit! Well, technically it was 2 days ago but I didn’t get around to posting anything because I was teaching a workshop. Funny enough, that workshop was about how I started and maintain my blog! 

On my one year anniversary, when I posted these Birthday Cake Oreo Fudge Brownies, I mentioned that the past year of blogging was not easy. I could definitely say that it’s been even harder the second year because I’ve been learning a whole lot of new things every single day and it’s been sort of stressful. 

Although it’s been stressful, I’m so incredibly grateful for all of the information I’ve been gathering from fellow bloggers. And compared to last year, things have skyrocketed! I plan on making a lot of great changes this year so once our 3rd anniversary arrives, things will be better than they’ve ever been! 

Flag Sheet Cake 

Though this is a big day for my blog, next week is a big holiday for both Canadians and Americans! First we got Canada Day then we’ve got Fourth of July a few days later! As a Canadian blogger, I gotta rep my country, but a majority of my readers are from the US so I gotta rep y’all too! 

So instead of making 2 separate desserts to celebrate our countries birthdays, I decided to bring them both together to make one great cake! 

This Flag Sheet Cake is so fluffy and moist and the sprinkle filling and red, white and red, white and blue frosting are a great festive touch! 

My ideas for this cake started off as a layer cake, but when it comes to outdoor celebrations like Fourth of July and Canada Day, no one wants to spend half the day preparing the food/dessert. 

Luckily, even though it may look a bit difficult, this cake is actually pretty easy to make. You make the cake batter, divide it and tint it your flags colours (optional), bake it, fill it with sprinkles, make the frosting, pipe on your flag! 

Most of these steps are completely optional, so if you only have a short amount of time, you could just bake a simple vanilla cake without changing the colours, skip the sprinkle filling, and just spread on the buttercream for a simple vanilla sheet cake!

Vanilla Cake

For this recipe, I used the same vanilla cake from my White Chocolate Raspberry Poke Cake recipe. The cake is the perfect combination of soft, fluffy, moist, tender and yummy! 

To get started, combine the dry ingredients in a medium bowl. The dry ingredients are simply all purpose flour, baking powder and salt. Then in a stand mixer bowl, beat the butter until it’s creamy. 

You could also use a large bowl and a hand mixer, but this recipe requires you to alternate between adding certain ingredients while the mixer is running, which I think is far easier to do when you have two hands free. 

Once the butter is creamy, keep the mixer running while you slowly pour in the sugar. When all of the sugar has been incorporated, continue beating until the mixture is nearly white and doubled in volume. 

Now add in the egg whites, one at a time. This is what makes the cake so fluffy! For the wet ingredients, add either milk or buttermilk to a liquid measuring along with sour cream, vegetable oil and vanilla extract and stir to combine. 

Alternate by adding the dry ingredients and the wet ingredients in multiple additions. This keeps the batter smooth throughout the mixing process. 

Red, White and Blue Cake

As I mentioned above, you could keep the cake plain. However, I like to go over the top so I divided the batter and tinted one portion red and another blue, then I left the rest plain white. 

One one side of the pan, I dolloped red, white and blue cake batter. On the other side, I dolloped red and white cake batter for the Canadian half. Then I used a butter knife to lightly swirl the colours together. 

If you’re doing an all American cake, you do this in the entire pan. And if you’re making an all Canadian cake, leave out the blue food colouring and just dollop red and white batter together. 

Surprise Sprinkle Filling 

Ooh, I love this part! Earlier this year I made a Sprinkle Surprise Cake for the Superbowl. For that cake, I created multiple sprinkle mixes using the colours of different football teams. 

I decided to do the same with this cake, because it really fits the theme of these holidays. Fun, festive, party, and firework celebrations! 

Canada Day Sprinkle Mix

I found a Canada Day themed sprinkle mix at my local cake supply store. However, if you can’t find a pre-made sprinkle mix, you could easily make your own. Just mix together an equal amount of red and white sprinkles. Then throw in some white sugar pearls, white sixlets, red sugar pearls, red sixlets, and red and white maple leaf sprinkles. 

If you’re in Canada, you should be able to find these at your local Bulk Barn and Party City.

Fourth of July Sprinkle Mix

Of course since I live in Canada, finding Fourth of July sprinkles is pretty much impossible, so I had to make my own. To do so, I combined red, white and blue sprinkles. 

Then I added some silver star confetti sprinkles, but if you could find edible silver stars, I definitely recommend adding those too! I also threw in some red and silver ball sprinkles.

I actually didn’t measure the amount of sprinkles, because I didn’t think it was necessary. You can add as much or as little sprinkles as you want. You’re almost definitely going to have more sprinkles than you need because each hole in the cake only needs about 1 tablespoon of sprinkles. 

To fill the cake, I used a large piping tip to core out holes in the cake. Make sure to save the cake you cut out and cut off the bottom part so you have a lid for the frosting to sit on. This is so the frosting and sprinkles don’t blend together. 

How to Decorate a Flag Cake

To decorate this flag cake, I started by making a batch of my super fluffy and creamy Vanilla Buttercream Frosting. Start by beating the butter in a large bowl using a stand mixer or hand mixer. 

You can use unsalted butter or salted butter. I like to use salted butter sometimes because the salt in the butter helps cut back the sweetness of the powdered sugar. If you use unsalted butter, you could achieve the same results by adding a bit of salt. 

How do I colour the Frosting?

I highly recommend you use red and blue gel food colourings instead of liquid food colouring. Especially since you’ll need to add a bit of red food colouring to achieve a nice deep red colour. The gel food colours allow you to add as much food colouring as you want without effecting the texture of the frosting. 

American Flag Frosting Design 

When all the frosting has been tinted, scoop each colour into a piping bag fitted with a piping tip of your choice. I used Wilton 6B, but you could use 1M, 8B or even a large round tip. 

To create the American flag decoration, I started by piping blue stars in a square in the corner. In the middle rows, I left a few empty spaces where I then piped in white stars. With the same white frosting, I piped the white lines in the American flag, then went back and did the same with the red frosting. 

Again, if you want this to be an all American cake, pipe this design over the entire thing instead of on one half. 

Canadian Flag Frosting Design 

The Canadian flag design was a bit more complicated since our flag has the maple leaf in the middle. As you can see, my maple leaf design was a bit uneven. I pulled up a picture of our flag on my phone and cropped it so I could use half of it as a reference, but my eyes were mainly on my phone so I didn’t notice how off it looked until it was too late. 

Still, anyone who looks at this cake could easily tell that it has the Canadian flag on it! 

Can I Make this Cake Ahead of Time?

If you have a lot of plans on Canada Day or the Fourth of July, you may not want to spend most of the day making the dessert. So you can definitely prepare this a day or two ahead of time! Just make sure to serve it at room temperature so the cake can retain its moist fluffy texture and the buttercream can be smooth enough to lick off the fork!

I’d love to know how these turn out for you, so if you make this recipe or any other recipe of mine, come back and leave a comment down below to tell me how they turned out!

And don’t forget to take photos and tag me on Instagram @queensleeappetit or use the hashtag #queensleeappetit so I could see your gorgeous creations!

More Great Canada Day and Fourth of July Recipes

No-Bake Canada Day Cheesecake

Red White and Blue Fudge Brownies

Baked Canada Day Donuts

Poutine Pizza

Honey BBQ Chicken Wings

Beer Burgers with Beer Cheese Sauce

The BEST Homemade Apple Pie

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Flag Sheet Cake

Yield: 12-15 slices

Prep Time: 1 hour 15 minutes

Cook Time: 35 minutes

Total Time: 1 hour 50 minutes

This Flag Sheet Cake will set off fireworks on your tastebuds! A moist vanilla cake tinted  to match each flags colours, patriotic sprinkles inside and a buttercream designed American flag on one side and a Canadian flag on the other. This is the perfect festive cake for both Canada Day and Fourth of July! 

Print

Ingredients

Vanilla Cake:

• 2 and 3/4 cups all purpose flour
• 1 Tbsp baking powder
• 1 teaspoon salt
• 1 cup unsalted butter, softened to room temperature
• 2 cups granulated sugar
• 6 large egg whites, room temperature
• 1 and 1/4 cups milk or buttermilk, room temperature
• 1/2 cup sour cream, room temperature
• 1/2 cup vegetable oil
• 1 Tbsp pure vanilla extract
• Red gel food colouring
• Blue gel food colouring

Fourth of July Sprinkle Mix:

• Red sprinkles
• White sprinkles
• Blue sprinkles
• Silver star sprinkles (or edible silver stars)
• Red pearl sprinkles
• Silver ball sprinkles

Canada Day Sprinkle Mix:

• Red sprinkles
• White sprinkles
• White sugar pearls
• White Sixlets
• Red sugar pearls
• Red Sixlets
• Red and white maple leaf sprinkles

Vanilla Buttercream:

• 2 cups Unsalted or salted Butter, softened
• 8 cups Powdered Sugar, sifted
• 1/2 cup Heavy Whipping Cream
• 1 Tbsp Pure Vanilla Extract
• 1/4 tsp salt (omit if using salted butter)
• Red gel food colouring
• Blue gel food colouring

Instructions

For the Vanilla Cake:

1. Position oven rack to the middle. Preheat oven to 350° F (177°C). Grease the bottom and sides of a 9x13 inch cake pan with nonstick spray. Set aside.
2. In a large bowl, sift the flour, baking powder and salt and whisk to combine. Set aside.
3. In the bowl of a stand mixer fitted with the paddle attachment, or in a large bowl using a hand mixer, beat the butter on medium speed until creamy, about 1 minute.
4. While the mixer is running, slowly pour in the sugar and continue to beat until light and fluffy, about 4-5 minutes.
5. Scrape down the sides and bottom of the bowl. Lower the speed to medium-low and mix in the egg whites, one at a time until completely combined.
6. Add the sour cream, oil and vanilla to the milk or buttermilk in a liquid measuring cup and whisk to combine, set aside.
7. Add 1/3 of the dry ingredients and beat just until combined, then add 1/2 of the liquid mixture and mix until just combined. Continue mixing in 1/2 of the remaining dry ingredients, remaining liquids, then remaining dry ingredients. Remember to mix after each addition before adding the next.
8. Scrape down the sides and bottom of the bowl again to make sure everything is mixed in properly.
9. If Making an American Cake: evenly divide batter between 3 bowls. Tint one bowl with red gel food colouring, then tint another bowl with the blue gel food colouring. Leave the last bowl plain.
10. Add batter to the pan, alternating between dollops of red, white and blue batter. Gently shake and tap the pan to settle the batter. You can use a butterknife to lightly swirl the colours, if you’d like.
11. If Making a Canadian Cake: divide the batter between two bowls. Tint one half with red gel food colouring and leave the other half plain. Repeat step 10.
12. Bake for 30-35 minutes or until a toothpick inserted into the center comes out clean.
13. Remove cake from oven and allow to cool completely on a wire rack.

For the Fourth of July and Canada Day Sprinkle Mix:

1. Combine the fourth of July sprinkles together in a small bowl. If making the Canadian version, mix the Canadian sprinkle mix sprinkles together.
2. There’s no measurements for this step, just throw the sprinkles together and it’ll look great!

Assembly:

1. Core holes on top of the cake using the bottom of a large piping tip, or an apple corer. Save the cut out cake pieces and cut off the bottom parts so your left with the flat top.
2. Spoon the sprinkle mix of your choice into the cake holes. Cover each hole with the flat cake tops.

For the Vanilla Buttercream:

1. In the bowl of a stand mixer, beat the softened butter until super pale and fluffy, about 5-6 minutes.
2. Scrape down the sides and bottom of the bowl. Add half of the powdered sugar, one cup at a time while beating on low speed until combined.
3. Add heavy cream and vanilla and continue to beat until combined and smooth.
4. Add remaining powdered sugar one cup at a time, mixing on low speed until it’s all incorporated.
5. Increase speed to medium-high and beat for about 5-7 minutes, or until frosting is light and fluffy.

How to Decorate an American Flag Cake:

1. Divide frosting between 3 bowls. Tint one red and another blue.
2. Spoon each colour into three large disposable piping bags each fitted with a large star tip.
3. Pipe on the flag design in a poof border motion (see my cake border piping tutorial for more info).
4. Start by piping an outline of the blue rectangle in the top left corner. When filling it in, leave some empty spaces where you want the stars to be.
5. Use the red frosting to pipe out the red stripes, leaving space in between each stripe for the white ones.
6. Use the white frosting to fill in the empty spaces in the blue rectangle to make the stars. Then pipe out the white part of the stripes. Enjoy!

How to Decorate a Canadian Flag Cake:

1. Divide frosting between 2 bowls. Tint one red and leave the other plain.
2. Spoon each colour into 2 large disposable piping bags each fitted with a large star tip.
3. Using the same technique mentioned above, start with the red frosting and pipe out the two red rectangles on each side of the flag.
4. Then pipe out the red maple leaf in the middle. It’s best to look at a picture of the Canadian flag for reference.
5. Use the white frosting to fill in the empty spaces. Enjoy!

Notes

- Cake can be made a day ahead of time. Cover and store in the refrigerator, serve at room temperature. Enjoy!

Recommended Products

As an Amazon Associate and member of other affiliate programs, I earn from qualifying purchases.

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  KitchenAid KSM155GBAZ 5-Qt. Artisan Design Series with Glass Bowl - Azure Blue
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  OXO Good Grips Non-Stick Pro Cake Pan 9 x 13 Inch
• 
  Wilton Decorating Tip, No.6B Star
• 
  Ateco 4712 Disposable Decorating Bags, 12-Inch, Pack of 100
• 
  Americolor Soft Gel Paste Food Color.75-Ounce, Red
• 
  KitchenAid KHM512IC 5-Speed Ultra Power Hand Mixer, Ice Blue
• 
  Royal Blue Icing Color (1 per Package)

BON APPÉTIT!

Love, Dedra

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