1. Crank your oven to 350°F and thoroughly grease and flour a 9×13-inch baking pan, or use that handy baking spray with flour already in it.

2. Whisk together flour, baking powder, and salt in a medium bowl. Set this aside and pretend you’re organized.

3. In your largest mixing bowl, cream butter and sugar together with an electric mixer on medium-high speed for about 3-4 minutes, until it’s so light and fluffy it practically doubles in volume. Don’t rush this step—it’s the secret to that tender crumb everyone loves.

4. Add eggs one at a time, beating well after each addition until fully incorporated. Splash in that vanilla extract and mix until combined. Your kitchen should smell like pure happiness right now.

5. Here’s the technique that matters: Add your flour mixture in three additions, alternating with milk in two additions, starting and ending with flour. Mix on low speed until just combined after each addition—some streaks of flour are okay! Overmixing is your enemy here.

6. Gently fold in those rainbow sprinkles by hand using a spatula. A few quick folds is all you need to distribute them evenly without overmixing the batter.

7. Pour batter into your prepared pan and spread it out evenly, giving the pan a couple gentle taps on the counter to release any air bubbles.

8. Slide into the oven and bake for 30-35 minutes, but start checking around 28 minutes because every oven is different. When a toothpick inserted in the center comes out clean or with just a few moist crumbs, you’re done.

9. Let the cake cool in the pan for about 10 minutes—if you can wait that long—then turn it out onto a wire rack to cool completely before frosting.

10. Once cooled, frost with your favorite frosting and shower with more rainbow sprinkles because more is more when it comes to celebration cakes.

Nutrition Information (Per Serving):

• Calories: 385
• Carbohydrates: 52g
• Protein: 5g
• Fat: 18g
• Fiber: 1g
• Sodium: 210mg
• Vitamin A: 15% DV
• Calcium: 8% DV

This cake provides energy for celebrations while the eggs and milk add quality protein. Enjoy as part of special occasions!

Notes:

• Seriously, use jimmies-style sprinkles (the rod-shaped ones), not nonpareils. Your cake will thank you by staying colorful instead of turning gray.
• Room temperature ingredients mix more easily and create better texture. Set your eggs and butter out about 30 minutes before baking.
• Every oven runs differently, so trust your eyes and that toothpick test over the exact timing.
• If your butter and sugar mixture looks separated after adding eggs, don’t panic—it’ll come together once you add the flour.
• This batter is on the thicker side, which is exactly what you want for a tender cake.

Storage Tips:

Store unfrosted cake tightly wrapped at room temperature for up to 2 days, or refrigerate frosted cake (covered) for up to 5 days. Don’t freeze with frosting on it—freeze just the cake layers wrapped tightly for up to 3 months. Microwaving makes it dry and sad, so let slices come to room temperature naturally.

Serving Suggestions:

• Classic Birthday Style: Top with vanilla buttercream frosting and extra rainbow sprinkles
• Ice Cream Sundae Cake: Serve warm with vanilla ice cream and hot fudge
• Trifle Style: Layer cake cubes with pudding, whipped cream, and fresh berries
• Breakfast Treat: Toast a slice and spread with butter for a special morning treat (no judgment here)

Mix It Up (Recipe Variations):

• Chocolate Funfetti: Replace 1/2 cup flour with unsweetened cocoa powder and add 1/2 cup chocolate chips
• Lemon Funfetti: Add zest of 2 lemons and replace 1/4 cup milk with fresh lemon juice for a bright, citrusy twist
• Vegan Funfetti: Use vegan butter, flax eggs (1 tablespoon ground flaxseed + 3 tablespoons water per egg, let sit 5 minutes), and plant-based milk
• Gluten-Free Funfetti: Use a 1:1 gluten-free flour blend designed for baking (Bob’s Red Mill works well)

What Makes This Recipe Special:

This homemade Funfetti cake uses traditional butter cake techniques that create superior texture and flavor compared to box mixes. The method of creaming butter and sugar, then alternating wet and dry ingredients, produces that coveted tender crumb while keeping rainbow sprinkles intact and colorful throughout.