Funfetti Sheet Cake is the perfect summer treat – vanilla cake laced with rainbow sprinkles and topped with a vanilla swiss meringue buttercream. Serve it for a crowd or keep it all to yourself!
Funfetti Sheet Cake
I think everyone can remember the boxed funfetti cake your mom would buy at the grocery store for your birthday cake. I always loved those, and let’s be honest here – they’re delicious. No shame on anyone for loving boxed cakes! But I will say – and I don’t think I really need to tell y’all this – homemade is just always better. With just about anything!
The other day I tried some pre-cut sugar cookie dough, and they were good, but they couldn’t compare to these sugar cookies. But that’s all beside the point. The point here is that we love funfetti sprinkles and we REALLY love cake around here. Put the two together and you get a magical cake!
What is Sheet Cake?
Sheet cake is just what it sounds like. Commonly they’re large cakes baked up in a sheet pan. This one is baked in a 13×9-inch pan, but the idea is that it’s a one-layer cake that’s topped with one layer of frosting.
I’ve had a lot of friends have a sheet cake in the back room at their weddings that resembles their actual tiered wedding cake, that way it’s much easier to cut up and share with your guests. Now don’t get me wrong – there’s a time and a place for beautiful layer cakes (like this vanilla layer cake), but there’s just something about a sheet cake that screams simplicity, and I LOVE simplicity.
I also want to add that sheet cakes have the perfect amount of frosting. If you’re like me and you really just want the cake with a touch of frosting, I think you’ll agree with me 🙂
What makes this cake special?
Y’all know I love a good cake or a good cupcake. But the reason I especially love this cake recipe is because we’re using the reverse creaming method. So when you go to bake the cake you’ll realize things are in a different order. Instead of creaming the butter and sugar together, then adding the dry ingredients and liquid ingredients a little bit at a time, we’re actually adding the dry ingredients straight into the bowl first, then adding everything in after that. Backwards, right?
The reverse creaming method is also referred to as the “paste method,” and you’ll realize very quickly why it’s called that when you’re preparing the batter. The beautiful thing about this method is that it lends a perfectly tender, velvety crumb, and a flat, less-domed cake.
Equipment you may need…
- Stand mixer: this is the one I have and I love it! I’ve had it for years now and I’ve never had any trouble with it. You definitely don’t “need” a stand mixer for this recipe, but it sure does make life a lot easier.
- Offset spatula: the best little utensil for almost any baking project. I find myself reaching for this one allll the time in the kitchen. It’s so helpful to use when spreading the frosting onto the cake.
- Measuring cups/spoons: I’ve been linking these in all of my posts because I love them SO much! They are beautiful and look just like some other expensive ones on the market (but wayyy cheaper).
- Mixing bowls: I love these glass mixing bowls from Amazon. They’re especially perfect for food photography.
Ingredients for Funfetti Sheet Cake
- All-purpose flour – I use King Arthur in my recipes always. I suggest using the same so your outcome is as similar as possible to mine!
- Baking powder
- Kosher salt – I use Diamond Crystal Kosher Salt always. This is also something I’d suggest using as the sodium content can vary across brands.
- Granulated sugar
- Unsalted butter
- Vegetable oil
- Egg whites – be sure they’re at room temperature!
- Sour cream
- Pure vanilla extract – now is not the time for artificial vanilla. Since this cake is all about the vanilla, I suggest using a high quality one!
- Whole milk
My Kitchen Tips
- Grease your pans really well. As my queen, Ina Garten, would say: “what’s the point of making a cake if you can’t get it out of the pan?” Ina knows, and we should always follow her advice. There’s nothing worse than spending time baking a homemade cake only to struggle to remove it from the pan… that’s why I make sure to spray mine with cooking spray, then line with parchment paper, then spray a little bit more. This will ensure a cake that slides out of the pan easy peasy.
- Read THIS blog post. If you’re making swiss meringue buttercream to frost your cake, be sure to read this blog post. I walk you through step-by-step how I do it, with photos and everything! It can be an intimidating process, but with a little help and attention to detail you too can enjoy one of the best buttercreams ever. I also have a step-by-step video tutorial over on my instagram stories. Just look for the “SMBC” highlight!
- Add extra sprinkles. Of course, we’re adding the sprinkles into our cake, but who says you can’t add more sprinkles to the top of the cake?! I’m all for adding sprinkles wherever I can!
- Use an American Buttercream, if you’d like. If Swiss Meringue is just not in the cards for you this time and you just want something quick and easy – use this vanilla buttercream recipe from my vanilla layer cake recipe. This is much faster and still delicious.
Can I make this cake ahead?
This cake is so versatile and great for serving a crowd because you can make both the frosting and the cake in advance. I like to bake the cake about 1 or 2 days before I serve it, wrap the cooled cake – still in the pan – completely in plastic wrap, and refrigerate it until I’m ready to frost it.
For the buttercream, you can make this the night before you serve it and cover it with plastic wrap. This buttercream is very stable at room temperature, so you can either leave it out overnight on the counter or refrigerate it, whichever you prefer. I just wouldn’t leave the frosting out for more than 1 night.
How to store
You can store this cake in an airtight container in the refrigerator for up to 5 days. It keeps really well and there’s something about cold cake that I just adore. You can also let it come to room temperature before you eat it though 🙂
I hope you all love this recipe as much as I do, and if you have any questions be sure to leave a comment or drop me a line at sarah@sarahsdayoff.com. And if you make this recipe, be sure to tag me @sarahsdayoff so I can see your beautiful cake 
Love,
Sarah
“Then if my people who are called by my name will humble themselves and pray and seek my face and turn from their wicked ways, I will hear from heaven and will forgive their sins and restore their land.” – 2 Chronicles 7:14 –
Funfetti Sheet Cake
Ingredients
For the Cake
- 2 1/4 cups (343g) all-purpose flour
- 1 Tbsp baking powder
- 1/2 tsp kosher salt
- 1 1/2 cups (374g) granulated sugar
- 3/4 cup whole milk at room temperature
- 3/4 cup sour cream at room temperature
- 1/2 cup unsalted butter at room temperature, sliced into Tbsp-sized pieces
- 1/4 cup vegetable oil
- 2 Tbsp pure vanilla extract
- 4 large egg whites at room temperature
- 1/3 cup rainbow sprinkles
For the Vanilla Swiss Meringue Buttercream
- 6 large egg whites
- 2 cups granulated sugar
- 1 1/2 cups (3 sticks) unsalted butter softened to about 63°F and cut into Tbsp-sized pieces
- 2 tsp pure vanilla extract
- 1/8 tsp kosher salt
Instructions
For the Cake
- Preheat oven to 350°F. Grease a 9x13-inch pan with cooking spray, and line with parchment paper. Spray top of parchment with more cooking spray.
- Add flour, baking powder, salt, and sugar to the bowl of a stand mixer fitted with the paddle attachment. Mix on low speed for about 10 seconds, just to combine the ingredients
- Combine the milk and sour cream in a large (2-cup) liquid measuring cup.
- Add butter slices, oil, vanilla, and half of the milk mixture to the bowl of the stand mixer. Beat on medium speed until the mixture looks slightly crumbly. Stop the mixer and scrape down the sides of the bowl.
- If you haven't separated your eggs already, crack the egg whites into the liquid measuring cup with the remaining milk/sour cream mixture (save the egg yolks for another recipe, like this French Silk Pie). Whisk to combine.
- With the mixer running on low speed, slowly add the milk mixture, in 2 additions, beating for 15 seconds in between each addition. Stop the mixer and scrape down the bowl once everything is incorporated.
- Add in the sprinkles and mix for an additional 15 seconds on medium speed. Pour batter into prepared pan. Bake 35 to 40 minutes or until the sides pull away from the pan and a toothpick inserted into the center of the cake comes out clean.
- Cool cake completely in pan. Once cooled, remove from pan and cool completely on a wire rack before frosting.
For the Vanilla Swiss Meringue Buttercream
- Make 1 batch of this Swiss Meringue Buttercream. If you don't want to make Swiss Meringue, feel free to make the Vanilla Buttercream from this cake recipe instead.
- Spread the frosting on the cooled cake, using a piping bag to pipe decorations, if desired. Sprinkle with additional sprinkles.
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