Funfetti Birthday Cake

This super moist and fluffy homemade funfetti cake recipe will remind you of all your childhood birthday parties. It’s filled with colorful rainbow sprinkles and topped with a soft American buttercream that makes for a perfect birthday cake for your next celebration. 

 

You may remember those Pillsbury funfetti boxed cake mixes that taste so good! This cake resembles those flavors, but tastes even better because it's from scratch! It uses soy lecithin, and xanthan gum to hold in more moisture than typical cake recipes but is better for layered cakes. This makes it perfect for slicing and cute cake photos at your next birthday party.

Funfetti Cake Ingredients

You might be surprised to see some of these ingredients but I researched all the ingredients on the back of a box of funfetti mix to reverse engineer this recipe. I left out the preservatives since we aren't making this cake for mass production but you might be surprised to know what some of these ingredients actually do.

Buttermilk: Buttermilk is great to add to cakes because it adds in extra moisture. The acidity breaks down the gluten in the all-purpose flour to keep your cake super soft. If you don't have buttermilk, you can make your own buttermilk substitute.

Shortening: Did you know shortening is an emulsifier? It helps recipes retain more moisture and keeps them tasting fresher! If you don't want to use shortening you can use all butter and reduce the buttermilk by 100g.

Xanthan Gum: I know, you think of xanthan gum and get scared because it’s an additive, but trust me, for this recipe you will need this. Xanthan gum is an emulsifier that mimics the form of gluten and will actually help your cake retain even more moisture than typical cake recipes and also strengthens the structure of the cake. You can find xanthan gum in the spice and baking aisle.

Soy Lecithin: Soy lecithin is also an emulsifier that you commonly find in chocolate. It helps fat and water combine easier which they normally don't do well on their own. Combining this with the xanthan gum will cause the funfetti cake to be rich and add extra moisture while still holding its shape. If you can't find soy lecithin you can leave it out but reduce your buttermilk by 100g.

Clear Vanilla Extract: This will help our cake and buttercream stay lighter in color. It’s commonly used in white cake to keep it white since regular vanilla has a dark color. If you don't have clear vanilla you can use any vanilla extract.

What Sprinkles To Use: For this recipe, you need to use the long-shaped sprinkles also known as Jimmies. I used Favorite Day’s rainbow sprinkles. You want to stay away from nonpareils or confetti sprinkles because those tend to bleed too much when baking.

Butter Flavor:  Butter flavor? Does that exist? Yes, it does, and it’s actually commonly used in grocery store cakes and your favorite movie theater popcorn. That buttery popcorn flavor is exactly what we are using to give this cake that traditional funfetti box mix taste! If you can't find butter extract then you can leave it out, but your cake will not taste exactly like funfetti box mix but it will still be delish.

Funfetti Cake Step By Step

1. Preheat your oven to 350ºF. Prepare three 8 inch cake pans with cake goop or another preferred cake release.
2. In a measuring cup, add in your buttermilk, oil, butter extract, and vanilla extract. Set aside. 
3. In a separate bowl, mix together your egg whites and whole eggs. Set aside. 
4. In the mixing bowl of your stand mixer, add in your cake flour, sugar, baking powder, salt, xanthan gum, soy lecithin, shortening, and butter. 
5. Mix on medium speed for 2-4 minutes or until the texture becomes crumbly.
6. While mixing on low speed, slowly stream in ⅔ of your buttermilk mixture (you should have about 4oz of liquid leftover).
7. Increase the speed to medium and mix for 2 full minutes to develop the cakes structure.
8. Reduce the speed to low then stream in your egg mixture and the rest of the buttermilk slowly until incorporated.
9. Mix everything together for 30 seconds until everything is homogeneous.
10. With a spatula, Fold in your sprinkles.
11. Divide your batter evenly into 3 pans. ( if making cupcakes divide evenly into liners, about 1-2 spoonfuls).
12.  Bake at 350º F for about 35-40 minutes ( about 18-20 minutes if you are making cupcakes).  

Buttercream Step By Step

1. Using the mixing bowl of your stand mixer with the whisk attachment, whisk your softened butter until smooth.
2. While mixing at a slow speed. Add in your powdered sugar one cup at a time and mix until smooth.
3. Add in your butter flavor, clear vanilla extract, and cream.
4. Whip for 2-3 minutes until buttercream is smooth.

Assembling The Funfetti Cake

1. Optional: Trim the brown layer of the top and sides of your cake layers. I usually trim my cakes because it gives them a cleaner look.
2. Place your cake on a cake board, or you can use a flat plate. 
3. Take a few scoops of buttercream onto your first cake layer and spread a thin even layer about ½  inch thick using an offset spatula.
4. Stack your second cake layer on top and repeat the process.
5. Stack your third cake layer on top of the second and spread a thin layer of buttercream around the whole cake. Scrape off any access buttercream to where you can almost see your cake layers through your buttercream with your offset spatula or a bench scraper. This is called a crumb coat.
6. Once you frosted your crumb coat, place your cake in the fridge or freezer for at least 15 minutes, or until your buttercream is firm to the touch. This allows the buttercream to harden, so when you go to decorate, your layers won't move around and your first layer of buttercream will act as a base coat for your next layer. 
7. Place your final coat of buttercream around your cake with your offset spatula, and smooth it out as much as best as you can.
8. Now, using your bench scraper, scrape away the excess frosting until it becomes as smooth as you can make it. Hold the scraper straight up and down, and slowly turn the cake until you’ve removed all of the excess buttercream This will give your cake straight edges.
9. Smooth out the top of your cake and remove any excess buttercream with an offset spatula. You can now decorate your cake!

Decorating The Funfetti Cake

1.  Start by placing the sprinkles of your choice into a small bowl. ( for decoration it does not matter what kind of sprinkles you use)
2. Pick up your cake from the bottom of the cake board and scoop sprinkles with your hand and brush them around the bottom sides of your cake. (Make sure to have a sheet pan underneath to collect the escapees).
3. Once you have your desired look, place your cake back onto your plate or turntable.
4. Prepare a piping bag with the piping tip of your choice ( I used a Wilton 2F ). Fill your piping bag with some buttercream. 
5. I’m piping a simple shell border but you can decorate any way you like.  
6. Top with more sprinkles and some birthday candles. 

Now your cake looks delicious and ready to eat before it even makes it to the party!

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