Spring Funfetti Cake Delight

My neighbor knocked on the door last March with a box of pastel sprinkles she'd found at a vintage baking supply shop, insisting I had to make something worthy of them. I'd never been the type to fuss with food coloring or worry about coordinating buttercream shades, but standing in my kitchen with those soft pink, blue, and yellow jimmies spread across the counter, I felt something shift. This cake became my answer to her enthusiasm—a celebration wrapped in butter and whimsy that somehow felt less intimidating than I'd expected.

I baked this for my daughter's coworkers one April, and watching them light up when they saw the swirled pastel frosting reminded me that food doesn't need to be complicated to spark joy. One woman asked for the recipe three times, and I realized the real magic wasn't the technique—it was permission to make something unapologetically pretty.

Ingredients

• All-purpose flour (2 1/2 cups): The foundation of this cake, and using the right amount matters more than you'd think—I learned this after a dense mishap taught me to measure by weight when possible.
• Baking powder and baking soda (2 1/2 tsp and 1/2 tsp): These work together to give the cake its signature tender crumb and that gentle spring in every bite.
• Salt (1/2 tsp): A pinch that you won't taste but absolutely will miss if it's not there, because it balances the sweetness in a way that feels almost invisible.
• Unsalted butter (1 cup for cake, 1 1/2 cups for frosting): Room temperature is non-negotiable here—cold butter won't cream properly, and you'll end up with a dense cake instead of the cloud you're after.
• Granulated sugar (1 1/2 cups): This dissolves into the butter to create that light, fluffy base that makes the whole cake tender.
• Eggs (4 large ones): Room temperature eggs emulsify better into the butter mixture, creating a smoother batter with better structure.
• Pure vanilla extract (2 tsp for cake, 2 tsp for frosting): The quality here matters—cheap vanilla tastes hollow, but real vanilla transforms the whole flavor profile into something warm and genuine.
• Whole milk and sour cream (1 cup milk, 1/2 cup sour cream): This combination creates moisture and tang that keeps the cake from tasting dry, and the sour cream adds a subtle richness.
• Rainbow sprinkles—jimmies specifically (2/3 cup): Regular nonpareils dissolve into the batter and bleed color everywhere, but jimmies stay whole and vibrant, I discovered this the expensive way.
• Powdered sugar for frosting (5 cups, sifted): Sifting removes lumps and makes the frosting smooth and glossy rather than grainy and dull.
• Food coloring gels (pastel pink, blue, yellow, purple): Gel colors create true pastels without watering down your frosting the way liquid food coloring does.

Instructions

Get your mise en place ready:

Pull your butter, eggs, milk, and sour cream out of the fridge about an hour before you start—room temperature ingredients mix together like they're meant to be friends. Preheat your oven to 350°F and prepare two 9-inch pans with a light grease and parchment paper.

Whisk the dry ingredients:

In a medium bowl, whisk together the flour, baking powder, baking soda, and salt until everything is evenly distributed. This step prevents lumps and ensures your leavening agents work uniformly.

Cream the butter and sugar:

Beat them together in a large bowl for about 3 minutes until the mixture looks pale and fluffy—you're incorporating air into the butter, which helps the cake rise. When you lift the beaters, it should fall in ribbons rather than clumps.

Add the eggs one by one:

Add each egg individually and beat well after each addition so it fully incorporates—this creates an emulsion that keeps everything bound together. The batter should look smooth and creamy after all four eggs are in.

Mix in the vanilla:

A quick pour and stir, but this is where the cake's personality starts to emerge in your kitchen's aroma.

Combine the milk and sour cream:

Whisk them together in a separate bowl until combined—they don't need to be perfectly smooth, just mixed.

Alternate wet and dry:

Add the flour mixture and milk mixture in three parts each, starting and ending with flour, mixing just until combined after each addition. Over-mixing develops gluten and makes the cake tough, so resist the urge to be thorough here.

Fold in the sprinkles:

Using a rubber spatula, gently fold in the rainbow jimmies until they're evenly distributed without crushing them. This is the moment that feels almost magical as the colors scatter through the vanilla batter.

Divide and bake:

Divide the batter evenly between your prepared pans and smooth the tops gently. Bake for 28–32 minutes, watching until a toothpick inserted in the center comes out clean—the kitchen will smell like a celebration.

Cool with patience:

Let the cakes rest in their pans for 10 minutes before turning them out onto cooling racks to cool completely. This prevents them from breaking apart while still warm.

Whip the butter until silky:

Beat the softened butter by itself for about 2 minutes until it's smooth and creamy—this is easier than you'd expect. Gradually add the sifted powdered sugar on low speed, then increase to high and beat until fluffy and light, about 2–3 minutes.

Add the milk and vanilla:

Pour in the milk, vanilla, and a pinch of salt, then beat on high until the frosting looks fluffy and spreadable. If it seems too thick, add milk a teaspoon at a time.

Tint with pastels:

Divide the frosting into four bowls and add a tiny drop of gel food coloring to each, stirring until you have soft, dreamy colors. The beauty of gel is that you get true pastels without watering anything down.

Decorate with freedom:

Once the cakes are completely cool, frost and stack them with your pastel buttercream, or dollop and swirl for a marbled effect. There's no wrong way to do this—let your hands do what feels right.

Save It

A friend brought her three-year-old to taste-test this cake, and the child pointed at the swirled frosting and said, 'It's like springtime on a plate.' I've made desserts that impressed people with technical skill, but this one made someone's daughter happy in the simplest way possible, and I've been chasing that feeling ever since.

The Sprinkle Situation

Not all sprinkles are created equal, and I learned this the hard way when I bought the cheapest option at the grocery store and watched my beautiful batter turn into a muddy, color-bleeding mess. Jimmies—those longer, rod-shaped sprinkles—stay whole and vibrant in the batter, while nonpareils dissolve and leach color. Spend the extra dollar or two on quality sprinkles from a baking supply shop; your cake will thank you with vivid pops of color instead of murky streaks.

Why Pastel Buttercream Changes Everything

Pastel frosting walks a line between elegant and playful that regular buttercream can't quite hit. The soft, muted colors feel sophisticated enough for a wedding shower but fun enough for a birthday party, and the fact that you can swirl multiple colors together adds a handmade, almost artistic quality to the finished cake. I've watched people choose this cake over fancier options just because of how it looks on the plate.

Variations and Troubleshooting

This cake's basic vanilla structure is forgiving enough to bend without breaking. Greek yogurt works beautifully in place of sour cream if you need a substitute, though it will shift the flavor slightly toward tanginess, which honestly isn't a bad thing. For cupcakes instead of layers, drop the batter into lined tins and reduce baking time to 22–24 minutes, checking a minute earlier than you'd expect. If your frosting seems grainy after you add the powdered sugar, it likely means the sugar wasn't sifted or your butter wasn't soft enough—just keep beating on low speed until it smooths out, which usually takes another minute or two.

• Freeze unfrosted cake layers for up to a week if you want to make this ahead and assemble closer to serving time.
• Pair this with sparkling Moscato, lemonade, or even a light iced tea to balance the sweetness perfectly.
• If gel food coloring is hard to find in your area, check online baking supply shops—they're worth the effort.

Save It

This cake has become my go-to when I want to make someone smile without overthinking the technique. It proves that simple can be spectacular when you pay attention to the details that actually matter.

Recipe FAQs

→ What makes the Funfetti cake moist?

The combination of whole milk and sour cream adds moisture and tenderness to the cake crumb.

→ How do I prevent sprinkles from bleeding colors?

Use high-quality jimmies sprinkles instead of nonpareils, as they maintain their color better during baking.

→ Can I substitute sour cream with another ingredient?

Greek yogurt works well as a substitute, providing similar moisture and tang without affecting texture.

→ How should the pastel buttercream be colored?

Divide the buttercream into portions and tint each with pastel food coloring gels for soft, festive hues.

→ What tools are needed for decoration?

An offset spatula or piping bags allow precise application and swirling of the multicolored buttercream on the cake.