Birthday cakes are my FAVORITE -
I mean, you usually have to stay more traditional for wedding or anniversary cakes, but when you’re making a friend’s birthday cake? There’s no reason NOT to go all out and do some crazy stuff!
This one’s pretty simple if you want it to be – confetti cake, the crazy rainbow filling is a bit time-consuming but totally optional, and the ganache+sprinkle drip is just straight-up fun!
You could leave it at that if you wanted and just make a rainbow birthday cake, but another super fun option is to grab some darker icing and a list of your birthday-person's favorite things and just go to town adding allllll of them to the cake! This is an especially great option if you have someone with TOO many favorite things to theme their cake with all of them!
I included my favorite vanilla layer cake recipe below, but funfetti cake mixes are an option if you’re looking to cut out some prep time! Video below....and then ON to the recipes!
Confetti Cake Layers:
Note - this is a slightly-simplified layer cake recipe from ChelSweets.com - I highly recommend checking out her site if you haven't before; it's amazing!!
3 1/4 c. all purpose flour
3 c. granulated sugar
2 1/2 t. baking powder
1 t. salt
1 cup unsalted butter (or 2 sticks) room temperature
2 t. vanilla extract
1 1/2 cups buttermilk, room temperature
1/8 cup (28 grams) vegetable oil
¾ cup rainbow jimmies sprinkles
Mix together all dry ingredients (flour, baking powder, sugar, and salt) in a stand mixer with a paddle until fully combined.
Mix chunks of room-temperature butter slowly into the dry mix, on a low speed. Continue to mix until no large chunks of butter remain, and the mixture becomes crumbly.
Pour in eggs and mix on low until just incorporated. Mix in the buttermilk in two installments, on a low speed. Add in vanilla and oil, and mix at a low speed until fully incorporated. Scrape down the sides of the bowl with a spatula, then beat on medium speed for about 30 seconds. Stir in rainbow sprinkles.
Divide batter evenly between the prepared cake pans (I find a kitchen scale helpful for this part). This guarantees your layers will bake to be the same height.
Bake for 32-36 (or until a skewer comes out clean). Allow to cool for 10 minutes, then run an offset spatula around perimeter of the pan to separate the cake from the pan. Place cake layers into the freezer for 45 minutes, to accelerate the cooling process.
Once the layers have fully cooled, the caramelized bits can be trimmed from the sides / top of the cake using a serrated knife if desired. Be sure the layers are completely cooled or chilled before trimming. If you try to trim the layers while they’re still warm, they will crumble apart.
Cream Cheese Buttercream Frosting:
8 oz (one package) cream cheese, softened
16 Tablespoons (two sticks) butter, softened
6-7 c powdered sugar
2-4 Tablespoons milk
1 T clear vanilla extract
1/4 t. salt
Option: (save and add later) – 1-2 drops each red, orange, yellow, green, and blue liquid or gel food color – if you want rainbow-colored cake filling!
Beat together softened cream cheese and butter; slowly add in powdered sugar alternating with milk until frosting reaches desired consistency. Add vanilla and salt and beat until well combined.
- 1 8- or 9-inch cardboard cake circle
- Small piping bag or drip bottle (for adding sprinkle drip)
- Large piping bag & small / large tips – I bought my favorite set of large piping tips & bags here
- ½ cup rainbow nonpareil sprinkles
- Cake leveler, cake turntable, offset spatula, bench scraper, and large rimmed pan or baking tray - not all 100% necessary but incredibly helpful!
- If adding ‘favorite things’ piping – black food gel + small piping bag + small round tip
Once your cakes are cool, level them (if needed/desired). This can be done with a cake leveler or a large serrated knife and a ruler. Place a smear of frosting on your cake circle (to keep the cake from sliding while you decorate it) and center your first cake layer in the center of the circle. Spread the layer with frosting (or if you want to fill with rainbow frosting, color about 1/3 c frosting with each of your gel colors. Pipe a rim of white frosting and pipe small dallops of rainbow frosting into the center to fill the cake). Whatever filling you’ve chosen, repeat the process with your remaining cake layers.
Now you're ready to crumb-coat . If you're unfamiliar with crumb-coating, it's just what it sounds like – spreading a thin layer of frosting over the entire outside of the cake to keep crumbs out of your final layer.
Once your crumb coat has set (this takes about 5-10 minutes in the fridge), add your final layer of frosting and smooth. I like to use an offset spatula and bench scraper for this part. Once your cake is covered, place it into the fridge or freezer to set the frosting, and so that the cake will set the ganache drips when you add them.
-1/3 c heavy cream
-1 c white chocolate chips
+ nonpareil sprinkles
Place heavy cream and white chocolate chips in a microwave-safe bowl, and microwave on 50% power in 30-second intervals until smooth, stirring in between.
When your ganache has cooled to a moderate temperature – it should feel slightly warm and still be fairly liquid – transfer it to a squeeze bottle or piping bag. A spoon will work if you don’t have either of those; I've just found spoons to be a little bit more difficult to work with.
Slowly drizzle ganache around the upper edge of your cake, pausing every inch or so to let more ganache fall in a drip down the side of the cake. You’ll need to work a bit quickly at this part – you don’t want the ganache to set before you’ve had a chance to add the sprinkles! I found it easiest to add 3-4 drips and then quickly toss on sprinkles before the ganache was set.
Of note – DON’T make my initial mistake and tilt the cake while the drip’s still running! You’ll get a wonky-sideways-running drip!
Once you’ve added sprinkles to all your drips, return cake to the fridge or freezer to set the drips.
Transfer some frosting to your large piping bag, and pipe a rim of swirls around the top edge of the cake. Add a few more sprinkles to your frosting swirls. More sprinkles= more better, right?
If you’re adding a list of ‘favorite things’ to the cake, it may help to pipe the longest words/phrases on first, to make sure you don’t run out of room. Smaller lettering than you think you’ll need always helps, and I practiced some of the long ones on a piece of foil first to make sure I could get all the letters in. Have fun!
Make this recipe? Let me know how it went - or find me on Instagram and tag @IntensiveCakeUnit in your photo!