Funfetti Bars

This is the viral Funfetti Bars formula: made from scratch cookie batter base, creamy topping, and rainbow sprinkles baked into every layer.

Love Bars? Try 4 Ingredient Lucky Charm Bars and Monster Cookie Bars.

Soft and Chewy Funfetti Bars for Parties and Birthdays

Too many funfetti bars over‑bake at the edges and turn rock‑hard by day two. This version stays tender and gooey for days, with that rich cake‑batter flavor and a satisfying bar texture instead of basic sheet cake. Very similar to Monster Cookie Bars texture.

Made from scratch, with buttercream frosting, and a generous handful of teal, purple and pink sprinkles in both layers, these are the kind of funfetti bars people beg you to bring again!

Why You'll Love These Funfetti Bars

• One‑bowl, no‑chill dough that goes straight into the pan, perfect for busy bakers and last‑minute celebrations.
• Ultra soft, chewy texture in the center with lightly golden edges, just like your favorite bakery blondie.
• Customizable with rainbow sprinkles, white chocolate chips, or a layer of vanilla frosting for frosted funfetti bars.
• Easy to slice and transport, so they're ideal for bake sales, birthday parties, potlucks, and school events.

Funfetti Bars Key Ingredients

• Butter: Softened butter is creamed with sugar to create air pockets, giving the bars a tender, light crumb and rich, buttery flavor.
• White sugar: Balances sweetness and structure so the bars set properly and don't become overly dense.
• Eggs: Bind the dough, add richness, and help the bars rise slightly without becoming fluffy cake.
• Vanilla: Deepens the classic funfetti flavor; vanilla bean paste or extract keeps the flavor warm and bakery‑style.
• All‑purpose flour: Forms the structure of the bars; too much leads to dry, crumbly bars, while too little makes them greasy and underbaked.
• Baking powder and soda: A small amount of both gives the bars a slight lift so they're soft instead of dense and heavy.
• Salt: Balances sweetness and enhances the buttery, vanilla notes so the bars taste complex, not flat.
• Rainbow sprinkles: Assorted sprinkles (stars, edible glitter, nonpareils, etc.) that keep their color and shape when baked; they create the funfetti look without bleeding.
• Buttercream Frosting: Powdered sugar, heavy cream, a pinch of salt and butter.
• Gel food coloring: Pink, Purple, Teal.

How to Make Funfetti Bars

This is an overview with step-by-step photos. Full ingredients, measurements & instructions are in the recipe card below.

1. Combine Dry Ingredients

In a medium bowl, whisk together the flour, baking powder, baking soda, salt. Set aside.

2. Cream Butter and Sugar

In a large bowl, using an electric hand mixer, cream together the softened butter and sugar on medium speed until fluffy (about 2 minutes).

3. Mix Eggs and Vanilla

Beat in the eggs, mixing well. Stir in the vanilla extract.

4. Make Batter and Add Sprinkles

Gradually add the dry ingredient mixture to the wet ingredients, mixing on low speed until just combined. Be careful not to overmix. Gently fold in the sprinkles with a silicone spatula.

5. Spread the batter into the pan.

The batter will be thick.

6. Bake

Bake for 25-30 minutes, or until the edges are lightly golden and a toothpick inserted into the center comes out clean (a few crumbs are fine).  Let the bars cool completely in the pan on a wire rack.

7. Make the Frosting

In a large bowl, using an electric mixer, beat the softened butter on medium-high speed until light and fluffy (about 2 minutes).

Gradually add the sifted powdered sugar, one cup at a time, beating on low speed until combined, then increasing to medium-high and beating well after each addition.

Add the vanilla extract and 2 tablespoons of cream and salt. Beat until light, creamy, and fluffy. If the frosting is too stiff, add more cream, one teaspoon at a time, until desired consistency is reached.

8. Divide the Frosting

Divide the buttercream evenly among three small bowls.

9. Color the Frosting

Add a drop of pink gel food coloring to one bowl, purple to another, and teal to the third. Stir each until the color is vibrant and evenly distributed.

10. Decorate the Base

Once the bars are completely cool, you can frost them. Dollop spoonfuls of the pink, purple, and teal frostings randomly over the surface of the cooled bars.

11. Swirl the Frosting Colors

Using an offset spatula or the back of a large spoon, gently swirl the colors together to create a marbled effect. Don't over do it because the colors will be muddy. You want distinct patches and swirls of each color.

12. Add Sprinkles on Top of Frosting

Sprinkle generously with your sprinkles.

13. Cut into Squares

Once the frosting is set, use the parchment paper overhangs to lift the bars out of the pan. Cut into squares or rectangles.

Pro Tips for the Best Funfetti Bars

• Make sure your butter is softened (not melted) for the best creaming results and texture.
• Measure flour accurately: Spoon flour into your measuring cup and level it off; packing flour too tightly leads to dry, cakey bars instead of chewy ones.
• Once you add the flour, mix only until it's just combined. Overmixing can lead to tougher bars.
• Don't overbake: Pull the funfetti bars from the oven when the edges are set and lightly golden but the center still looks soft; they continue to cook as they cool and will firm up.
• Make sure the base is completely cooled before frosting. Frosting warm bars will lead to melted, sad frosting.
• Chill for cleaner slices: For ultra‑neat edges, chill the cooled funfetti bars in the fridge briefly before slicing, then let them come back to room temperature for serving.

Why are my funfetti gooey bars too runny or won't set?

• The bars were likely cut before they cooled completely, so the sweetened condensed milk layer was still molten.
• The center may be slightly underbaked if the edges are barely golden but the middle is very pale.

Why are my funfetti bars dry or not gooey?

• The bars were overbaked until golden all the way across instead of just at the edges.

Can I use a Different Frosting?

Yes! A simple vanilla cream cheese frosting will turn plain cookie bars into thick frosted funfetti bars, and it's perfect for decorating with more sprinkles.

Can I double the recipe for a crowd?

Yes, you can scale funfetti bars up for a sheet pan; spread the dough in an even layer and extend the bake time slightly until the center is just set.

Do I have to chill the dough?

No, one of the biggest advantages of funfetti cookie bars is that the dough goes straight into the pan and into the oven-no chilling required.

Can I use a cake mix instead of making them from scratch?

Yes, you can use boxed cake mix combined with butter, egg, and cream to form a bar dough, then top it with frosting and sprinkles.

How do I keep funfetti bars soft?

Avoid overbaking, store them airtight, and don't skip on sugar in the dough to help hold moisture and keep the bars chewy.

What sprinkles work best in funfetti bars?

Use rainbow jimmies for the batter and reserve specialty shapes, stars, or nonpareils for decorating the top after baking.

My sprinkles melted, bled, or disappeared

• Use high‑quality rainbow jimmies instead of nonpareils; they hold their shape and color better in the oven.
• Gently fold sprinkles in at the end of mixing instead of over‑mixing, which can smear the color.

Why is my dough crumbly and hard to press into the pan?

• The dry ingredients, butter, and egg were not mixed long enough; this dough takes a while to come together.
• The butter may have been too cold, so it didn't cream into the mix properly.

Pro Tip: Keep mixing until the mixture turns into a thick cookie dough; it can take several minutes, especially with a hand mixer.

Storage

Store leftover bars in an airtight container at room temperature for up to 3 days, or in the fridge for up to 5 days (let come to room temperature slightly before serving if refrigerated, as the base will be firmer).

More Sweet Bars to enjoy

• Raspberry Swirl Lemon Bars
• Cranberry Bliss Bars
• Strawberry Crumb Bars
• Cranberry Pecan Bars