OK here we GO. Welcome to Day 1 of Birthday Cake Bake Week, and we are kicking it off with the cake that started the whole obsession. A three tiered Funfetti Birthday Cake with a fresh raspberry filling and the dreamiest white chocolate buttercream you have ever put in your mouth. I made this for my 27th birthday and I am not exaggerating when I say it was the most PERFECT cake ever. Like, I cried a little. It was that good.
Funfetti has always had a chokehold on me. There is just something about a buttery, vanilla soaked cake stuffed with rainbow sprinkles that makes you feel 8 years old in the best possible way. But I wanted to give it a grown up moment, so I added a tart raspberry filling between the layers to cut through all that sweetness, and topped it off with a white chocolate buttercream that is somehow both rich AND light. The combo is INSANE. Sweet, tart, creamy, sprinkly, all the things.
This cake is for birthdays, OBVIOUSLY, but it is also for any moment that deserves to feel like a celebration. Got a promotion? Make this cake. Closed on a house? Make this cake. Survived a hard week? Definitely make this cake. Three tiers of joy is always the answer, no matter the occasion.
P.S. Use REGULAR rainbow sprinkles, not jimmies. Jimmies bleed their color into the batter and you end up with a weirdly tinted gray cake instead of a pretty white cake with bright sprinkle flecks. Trust me on this, I learned the hard way. Also, do not skip the simple syrup soak step at the end. It is what takes this cake from good to legitimately the moistest cake of your life.
Ingredients Needed
Unsalted Butter Used in the cake AND the buttercream, so make sure you have plenty on hand. Always go unsalted so you can control the salt yourself. Pull it out an hour ahead of time so it is properly softened, cold butter will not cream up fluffy.
Granulated Sugar The base sweetener for the cake and the raspberry filling. Plain white granulated gives you that clean sweetness that lets the vanilla and sprinkles shine.
Vegetable Oil This is my secret to a moist cake that stays moist for days. Butter alone can make cakes dry out faster, but adding oil keeps things tender even on day 3. Canola or any neutral oil works great too.
Eggs and Egg Whites Three whole eggs plus three extra whites at room temperature. The extra whites give the cake that classic light, fluffy, white cake texture (instead of a yellow buttery crumb). Room temp is non negotiable, cold eggs will seize up the butter and ruin the texture.
Vanilla Extract Pure vanilla extract throughout, in the cake AND the buttercream. Vanilla is the soul of a funfetti cake so this is not the time to use imitation.
Buttermilk or Whole Milk Buttermilk gives you the most tender, slightly tangy crumb and is what I always reach for. Whole milk works too if that is what you have. Avoid skim or 2 percent, you need the fat for richness.
Sour Cream My ride or die for ridiculously moist cakes. The fat and acidity tenderize the crumb and keep this cake soft for days. Do not skip it.
All Purpose or Cake Flour Either works! Cake flour gives you the most delicate, tender crumb (very classic bakery vibe). All purpose gives you a slightly sturdier cake that holds up beautifully under all those layers and frosting. Both are delicious, your call.
Baking Powder and Baking Soda Both leaveners are needed here. Baking powder gives the lift, baking soda reacts with the buttermilk and sour cream for extra tenderness and a perfectly even rise.
Salt Just one teaspoon, but it makes ALL the flavors pop. Without it, your cake will taste flat and one note even with all the vanilla and sprinkles.
Rainbow Sprinkles Use REGULAR rainbow sprinkles, the round little ones, NOT jimmies (the long skinny ones). Jimmies bleed their color into the batter and you will end up with a weirdly tinted gray cake. Wilton makes great rainbow sprinkles that hold their color beautifully.
Fresh or Frozen Raspberries Either one works for the filling, no need to thaw if frozen. Fresh raspberries give you the brightest flavor but frozen are way more accessible and budget friendly, especially out of season.
Lemon Juice Just one tablespoon (about half a lemon) but it is the key to making the raspberry filling taste vibrant instead of jammy. Always use fresh, bottled lemon juice has a weird metallic note.
Cornstarch A tiny teaspoon to thicken the raspberry filling so it stays put between the cake layers instead of sliding everywhere when you cut into it.
Heavy Cream For the buttercream. The cream is what makes this frosting so unbelievably light and silky. Do not swap for milk, you need the full fat to whip it up dreamy.
Powdered Sugar Sweetens and stabilizes the buttercream. Add it slowly and taste as you go, you may need a little more or less depending on how sweet you like things.
White Chocolate Use a good quality white chocolate bar (Ghirardelli or Lindt are great), NOT white chocolate chips. Chips have stabilizers that can keep them from melting smoothly. Melt it gently and let it cool slightly before adding to the buttercream.
Substitutions and Modifications
- Swap the raspberry filling for strawberry, blackberry, or even a lemon curd for different vibes
- No buttermilk? Mix 1 1/4 cup whole milk with 1 1/4 tablespoon lemon juice or white vinegar and let sit for 5 minutes
- Greek yogurt can sub for sour cream in a pinch, but full fat sour cream is best
- For a 2 layer cake, divide all the cake ingredients by 2/3 and use two 8 or 9 inch pans
- Skip the white chocolate in the buttercream for a classic vanilla buttercream (still delicious!)
- A 1 to 1 gluten free flour like Bob’s Red Mill or King Arthur works in the cake
Why You’ll Love This Recipe
- A three tiered showstopper that looks like it came from a high end bakery but is totally doable at home
- The fresh raspberry filling cuts through the sweet vanilla cake and white chocolate buttercream PERFECTLY
- Works for literally any celebration, birthdays, anniversaries, graduations, or just because you deserve cake
Equipment Needed
- Three 8 inch or 9 inch round cake pans so you can bake all three layers at once instead of doing it in batches.
- Stand mixer or hand mixer with paddle and whisk attachments for the cake batter (paddle) and the buttercream (whisk).
- Mixing bowls in a few sizes for whisking dry ingredients separately and for combining the raspberry filling.
- Small saucepan for cooking down the raspberry filling and for the optional simple syrup.
- Whisk for combining your dry ingredients and for stirring the raspberry filling smooth.
- Rubber spatula for gently folding in the dry ingredients and the sprinkles without deflating the batter.
- Parchment paper for lining the bottoms of your cake pans so the layers release cleanly.
- Wire cooling rack for cooling the cakes completely before assembly (this is non negotiable).
- Offset spatula for spreading the buttercream smoothly between layers and around the outside of the cake.
- Cake turntable if you have one, makes frosting the outside of the cake SO much easier.
Funfetti Birthday Cake with Raspberry Filling
Video
Ingredients
For the Funfetti Cake
- 1 cup unsalted butter softened to room temp
- 2 cups granulated sugar
- ½ cup vegetable oil
- 3 large eggs room temperature
- 3 large egg whites room temperature
- 1 tbsp vanilla extract
- 1 ¼ cup buttermilk or whole milk room temperature
- ¼ cup sour cream room temperature
- 3 ¾ cups all purpose flour or cake flour
- 2 tsp baking powder
- ½ tsp baking soda
- 1 tsp salt
- ¾ cup rainbow sprinkles NOT jimmies
For the Raspberry Filling
- 1 ½ cups fresh or frozen raspberries
- ½ cup granulated sugar
- 1 tbsp fresh lemon juice about 1/2 a lemon
- 1 tsp cornstarch
For the White Chocolate Buttercream
- 1 ¼ cups unsalted butter room temperature
- ¼ cup heavy cream
- 4 to 5 cups powdered sugar
- ½ cup white chocolate melted and slightly cooled
- 1 tsp vanilla extract
Optional Simple Syrup Soak
- ¼ cup granulated sugar
- ¼ cup water
Instructions
- Preheat oven to 350°F. Grease three 8 inch or 9 inch round cake pans with butter or oil, then line the bottoms with circles of parchment paper for easy release.
- Make the cake batter. In a stand mixer fitted with the paddle attachment, beat the softened butter and granulated sugar together on medium speed for a full 5 minutes, until pale and very fluffy. Do not skimp on this time, it is what gives you a light, tender crumb.
- Add the vegetable oil and beat for another 1 minute until fully combined.
- Add the eggs, egg whites, and vanilla extract. Beat for 1 more minute, scraping down the sides as needed.
- Add the buttermilk and sour cream and beat for 1 minute until smooth. The batter may look slightly broken, that is totally fine.
- In a separate bowl, whisk together the flour, baking powder, baking soda, and salt. Gently fold the dry ingredients into the wet ingredients with a rubber spatula until JUST combined, do not overmix or the cake will be tough.
- Gently fold in the rainbow sprinkles, working quickly so they do not bleed.
- Divide the batter evenly between the three prepared pans (a kitchen scale really helps here for even layers). Bake at 350°F. For 8 inch pans, bake 24 to 28 minutes. For 9 inch pans, bake 22 to 24 minutes. After 15 minutes, gently tent each pan with aluminum foil so the tops do not get too brown. Cakes are done when a toothpick inserted in the center comes out clean.
- Let the cakes cool in the pans for 10 minutes, then turn out onto a wire rack to cool COMPLETELY, at least 1 hour. Do not even THINK about frosting a warm cake.
- While the cakes bake, make the raspberry filling. In a small saucepan over medium heat, combine the raspberries, granulated sugar, and lemon juice. Bring to a gentle simmer and cook for about 10 minutes, stirring occasionally and breaking up the raspberries with the back of a spoon as they soften.
- In a tiny bowl, stir the cornstarch with 1 tablespoon of cold water to make a slurry, then whisk it into the simmering raspberries. Cook for another 1 to 2 minutes, until thickened. Pour into a heat safe bowl and let cool completely. It will continue to thicken as it cools.
- Make the optional simple syrup. In a small saucepan, combine 1/4 cup sugar and 1/4 cup water. Bring to a simmer, stir until sugar dissolves, then remove from heat and let cool. This is the secret to ULTRA moist cakes, brush a generous amount on each cake layer before assembling.
- Make the white chocolate buttercream. In a stand mixer fitted with the whisk attachment, beat the room temp butter on medium-high speed for 3 minutes, until light and fluffy. Alternate adding the heavy cream and powdered sugar, beating well after each addition.
- Add the melted (and slightly cooled) white chocolate and vanilla extract. Beat until light and fluffy. Add more powdered sugar if too thin or more heavy cream if too thick, until you reach a smooth, pipeable consistency.
- Assemble. Place the first cake layer on a cake stand or plate. Brush generously with simple syrup if using. Pipe a thick ring of buttercream around the edge of the layer (this acts as a dam). Spoon raspberry filling into the center, spreading it gently, then top with a thin layer of buttercream.
- Add the second cake layer. Brush with simple syrup, pipe a buttercream dam, fill with raspberry filling, and top with buttercream. Repeat with the third layer.
- Frost the top and outside of the cake with the remaining buttercream. Decorate with extra rainbow sprinkles around the base or all over the top for that signature funfetti vibe. Slice, serve, and CELEBRATE!
Storage Instructions:
- Counter: Store the assembled cake at room temperature under a cake dome or loosely covered for up to 1 day.
- Fridge: Store in an airtight cake keeper or loosely covered with plastic wrap in the refrigerator for up to 4 days. Let sit at room temp for 30 minutes before serving to soften the buttercream.
- Freezer: Wrap individual unfrosted cake layers tightly in plastic wrap and freeze for up to 2 months. Thaw at room temp before assembling. Fully assembled slices can also be frozen wrapped in plastic for up to 1 month.
Tips and Tricks
- The 5 minute butter and sugar creaming time is non negotiable. This is what creates all those tiny air pockets that give you a light, tender cake.
- Use a kitchen scale to divide the batter evenly between pans. Even layers bake at the same rate and look way more professional.
- Make sure your raspberry filling is COMPLETELY cool before assembling or it will melt the buttercream and slide everywhere.
- A buttercream dam (a thick ring of frosting around the edge before adding filling) is the key to keeping the raspberry filling tucked inside the cake instead of oozing out the sides.
FAQ
Can I make this cake ahead of time?
Yes! Bake the cake layers up to 2 days ahead, wrap them tightly in plastic wrap, and store at room temperature. The raspberry filling and buttercream can both be made 1 day ahead and stored in the fridge. Let everything come to room temp before assembling.
Why did my cake come out gray instead of white with sprinkle flecks?
You used jimmies instead of regular rainbow sprinkles! Jimmies have a coating that bleeds when mixed into batter. Use the round, harder rainbow sprinkles (Wilton or similar brand) for that classic funfetti look.
Can I make this as a 2 layer cake instead of 3?
Yes, just multiply all the ingredients by 2/3 and bake in two 8 or 9 inch pans. Keep an eye on the bake time as 2 layers may take a couple minutes longer.
What if my buttercream is too sweet?
Add a pinch of salt and a small splash of heavy cream. The salt cuts the sweetness and the cream loosens it up beautifully. You can also beat in an extra tablespoon of softened butter for richness.
Can I use white chocolate chips instead of a bar?
Technically yes, but bars melt more smoothly. Chips contain stabilizers that can make them seize up when melted, so if that is all you have, melt them very gently and slowly with a tiny splash of cream.
Can I make this gluten free?
Yes, swap the flour with a 1 to 1 gluten free baking flour like Bob’s Red Mill or King Arthur. The texture will be slightly more delicate but still totally delicious.
Do You LOVE Making Cakes?! Check Out More of my Favs:
Salted Caramel Brown Butter Carrot CakeÂ
Triple Chocolate Cake with Chocolate Cream Cheese Frosting
Brown Butter Pumpkin Coffee Cake with Maple Cinnamon GlazeÂ
Let’s Connect!
If you make this Funfetti Birthday Cake, PLEASE tag me on Instagram and TikTok @munchiesbymallory! I am genuinely OBSESSED with this cake and Birthday Cake Bake Week is just getting started. Drop a comment below and tell me what celebration you are baking this for, I love living vicariously through your parties. Eat your cake and drink it too! Love you guys! xoxo
Leave a Reply