Introduction
Unicorn Bars are a delightful and eye-catching treat that’s perfect for parties, birthdays, or any occasion that calls for a touch of magic. These bars feature a rich and fudgy brownie base, topped with a creamy buttercream frosting and adorned with a vibrant rainbow of sprinkles. They’re not only delicious but also incredibly fun to make, making them a great baking project to do with kids.
Anecdotal Story
I first made these Unicorn Bars for my daughter’s birthday party, and they were a huge hit! The kids were mesmerized by the colorful sprinkles and the whimsical design. The bars disappeared in a flash, and I received countless requests for the recipe. These bars have become a staple for our celebrations, bringing smiles and joy to everyone who tries them.
Ingredient Descriptions
Brownie Layer
- Butter: Adds richness and moisture to the brownie base. Make sure to use softened butter for easy mixing.
- White Chocolate: Gives the brownie base a creamy texture and a subtle sweetness. Use good quality white chocolate for the best flavor.
- Granulated Sugar: Sweetens the brownie base and contributes to its fudgy texture.
- Eggs: Bind the ingredients together and add structure to the brownie base.
- All-Purpose Flour: Provides the structure and texture of the brownie base.
- Vanilla Extract: Adds a warm, sweet flavor to the brownie base.
- Salt: Enhances the overall flavor of the brownie base and balances the sweetness.
- Rainbow Sprinkles: Add a pop of color and a playful touch to the brownie base.
Buttercream Frosting
- Butter: Adds richness and creaminess to the frosting. Make sure to use softened butter for easy mixing.
- Powdered Sugar: Sweetens the frosting and gives it its smooth texture.
- Heavy Cream: Adds moisture and helps to create a smooth and spreadable consistency.
- Red and Blue Food Coloring: Used to tint portions of the frosting blue and purple for the unicorn design. Use gel food coloring for more vibrant colors.
- Rainbow Sprinkles: Add a final touch of color and whimsy to the decorated bars.
Equipment/Tools
- 13×9-inch Baking Dish: For baking the brownie base.
- Parchment Paper (Optional): To line the baking dish for easy removal and cleanup.
- Saucepan: For melting the butter and white chocolate.
- Mixing Bowls: For mixing the brownie batter and the frosting.
- Hand Mixer or Stand Mixer: For blending the ingredients together.
- Spatula: For scraping down the sides of the bowl and spreading the batter.
- Wire Rack: For cooling the brownie base.
- Cake Tester or Toothpick: To check for doneness.
- Decorator Bags (Optional): For piping the blue and purple frosting lines.
- Sprinkles: For decorating.
Complete Recipe
Ingredients with Measurements
Brownie Layer
- 1 cup butter, softened
- 10 ounces white chocolate, chopped
- 1 ¼ cups granulated sugar
- 4 large eggs
- 2 cups all-purpose flour
- 1 tablespoon vanilla extract
- ½ teaspoon salt
- ½ cup rainbow sprinkles
Buttercream Frosting
- 1 cup butter, softened
- 4 cups powdered sugar
- 3 tablespoons heavy cream
- 3 drops red food coloring
- 3 drops blue food coloring
- ½ cup assorted rainbow sprinkles for decorating

Step-by-Step Instructions
Brownie Layer
- Grease a 13×9-inch baking dish or line with parchment paper.
- Preheat oven to 325°F.
- Place butter and chopped white chocolate in a saucepan. Melt over low heat, stirring occasionally.
- Let cool for 10 minutes.
- Add in granulated sugar and stir until well-combined.
- Add in eggs, one at a time, stirring well after each one is added.
- Stir in all-purpose flour, salt, and vanilla. Mix until well-combined.
- Stir in the sprinkles.
- Bake in a 325°F oven for 30 to 35 minutes until a cake tester comes out clean.
- Cool completely on a wire rack before frosting.
Buttercream Frosting
- In the bowl of a stand mixer, or a mixing bowl with a hand mixer, beat butter for two minutes.
- Slowly add in powdered sugar, alternating with cream, adding 1 to 2 tablespoons of cream at a time.
- Add in vanilla and beat until smooth. (About 2 minutes).
- Set aside ½ cup of frosting and tint with blue food coloring.
- Take half of the blue icing and place in a separate bowl. Add red food coloring to make purple icing.
- Frost cooled bars completely with remaining white icing.
- Place blue and purple icing in separate decorator bags.
- Pipe diagonal blue lines across the blondies.
- Pipe purple lines diagonally across going the opposite direction to form a diamond pattern.
- Top with sprinkles and enjoy!

Troubleshooting Common Problems
- Brownies are too dry: Make sure not to overbake the brownies. Check for doneness with a toothpick or cake tester.
- Frosting is too thick: Add more heavy cream, a teaspoon at a time, until you reach the desired consistency.
- Frosting is too thin: Add more powdered sugar, a tablespoon at a time, until you reach the desired consistency.
Tips and Variations
- Use different sprinkles: Get creative with the sprinkles! You can use different colors, shapes, and sizes.
- Add different flavors: You can add extracts like almond or peppermint to the brownie batter or the frosting.
- Make it chocolatey: Use milk chocolate or dark chocolate instead of white chocolate for the brownie base.
- Drizzle with melted chocolate: Drizzle melted white chocolate or colored candy melts over the frosted bars for an extra touch of sweetness and decoration.
Serving Suggestions
- Cut the bars into squares or rectangles and arrange them on a platter for a beautiful presentation.
- Serve the bars as part of a dessert table for a party or celebration.
- Package the bars individually in cellophane bags and tie with ribbon for gifts.
Pairing Recommendations
- Drinks: A glass of milk or a cup of coffee pairs perfectly with the sweetness of the bars.
- Desserts: Serve the bars alongside other unicorn-themed treats like cupcakes, cookies, or cake pops.
Nutritional Information (Approximate)
(Nutritional information will vary depending on the specific ingredients used.)
Comprehensive FAQ
- Can I use a different type of frosting? Yes, you can use any type of frosting you like, such as cream cheese frosting or chocolate frosting.
- Can I make these bars ahead of time? Yes, you can bake the brownie base and make the frosting a day ahead of time. Assemble the bars the day you plan to serve them.
- How do I store leftover bars? Store leftover bars in an airtight container at room temperature for up to 3 days or in the refrigerator for up to a week.
Unicorn Bars: A Magical Rainbow Treat
Description
These Unicorn Bars are a whimsical and delicious dessert that will bring a touch of magic to any occasion! With a fudgy brownie base, creamy buttercream frosting, and vibrant rainbow sprinkles, they’re a guaranteed crowd-pleaser. Get the full recipe and bake some happiness
Ingredients
Brownie Layer
- 1 cup butter, softened
- 10 ounces white chocolate, chopped
- 1 ¼ cups granulated sugar
- 4 large eggs
- 2 cups all-purpose flour
- 1 tablespoon vanilla extract
- ½ teaspoon salt
- ½ cup rainbow sprinkles
Buttercream Frosting
- 1 cup butter, softened
- 4 cups powdered sugar
- 3 tablespoons heavy cream
- 3 drops red food coloring
- 3 drops blue food coloring
- ½ cup assorted rainbow sprinkles for decorating
Instructions
Brownie Layer
- Grease a 13×9-inch baking dish or line with parchment paper.
- Preheat oven to 325°F.
- Place butter and chopped white chocolate in a saucepan. Melt over low heat, stirring occasionally.
- Let cool for 10 minutes.
- Add in granulated sugar and stir until well-combined.
- Add in eggs, one at a time, stirring well after each one is added.
- Stir in all-purpose flour, salt, and vanilla. Mix until well-combined.
- Stir in the sprinkles.
- Bake in a 325°F oven for 30 to 35 minutes until a cake tester comes out clean.
- Cool completely on a wire rack before frosting.
Buttercream Frosting
- In the bowl of a stand mixer, or a mixing bowl with a hand mixer, beat butter for two minutes.
- Slowly add in powdered sugar, alternating with cream, adding 1 to 2 tablespoons of cream at a time.
- Add in vanilla and beat until smooth. (About 2 minutes).
- Set aside ½ cup of frosting and tint with blue food coloring.
- Take half of the blue icing and place in a separate bowl. Add red food coloring to make purple icing.
- Frost cooled bars completely with remaining white icing.
- Place blue and purple icing in separate decorator bags.
- Pipe diagonal blue lines across the blondies.
- Pipe purple lines diagonally across going the opposite direction to form a diamond pattern.
- Top with sprinkles and enjoy!