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These fun & magical Mermaid Cookie Bars are so pretty, bejeweled with pastel colored m&m’s, buttercream frosting, fancy sparkly sugar & sprinkles galore! We even added some white chocolate chips in our mermaid cookie bars recipe!

These tasty bars are perfect for your mermaid birthday party and fun party snacks for pool/beach parties and BBQs! They will definitely be the hit of the party!

I made these Mermaid Cookie Bars on a whim, when I had an abundance of pastel m&m’s leftover after making some M&M Easter Cookies the other day.

They were super yummy! Besides, who doesn’t love homemade cookie bars all decorated up with sparkles and goodies on top? Perfect when you’re looking for mermaid party ideas!

Feel free to change up the color of your frosting and the theme of your sprinkles. These bars can be made to match just about any holiday or event you might be celebrating!

I got my sprinkles from Fancy Sprinkles. I used the Cotton Candy Sprinkles and the Haunted Mansion Sugar, but they have tons of glimmering sugars and sprinkles you can browse through. They do have a cool Mermaid Cove Sprinkle Medley that would be awesome on these too!

Mermaid Inspiration

I’ve always been fascinated with mermaids and mythology. Mermaids go back thousands of years and was first referenced in ancient Assyria, when the Assyrian goddess Atargatis turned herself into a mermaid. She was believed to be the inspiration around the world for thousands and thousands of years. She was the goddess of the moon, feminine powers and water and was worshipped 4000–3000 years ago in ancient Assyria and later on all over the Mediterranean.

As far as mermaids in my lifetime, I’m most familiar with Hans Christian Anderson’s 1836 tale, The Little Mermaid, the remake of Disney’s 1989 film The Little Mermaid, and Darrell Hannah in Splash. Aqua Man (Mermen and Mermaids) and Aquamarine also are really good movies!

Ingredients You Need

Sugar Cookie Bars

unsalted butter
granulated sugar
brown sugar
eggs
vanilla extract
all purpose flour
baking soda
baking powder
salt

Easy Buttercream Frosting

butter
powdered sugar
vanilla extract
milk of choice
Food coloring or gel – purple, blue, pink or green are good option colors

Mermaid Extras

Pastel m&m’s, sprinkles, sugars of choice that are Mermaid inspired colors like blue, purple and green mainly and go perfectly on these mermaid dessert bars!

How to Make Mermaid Sugar Cookie Bars

Cookie Bars

Preheat oven to 350 degrees. Line a 9 x 13 inch baking dish with parchment paper or spray with nonstick cooking spray and set aside.
In a large bowl, beat together butter and sugars with an electric mixer until light and fluffy for about 3-5 minutes. Beat in the eggs and vanilla until smooth.
In a small bowl, sift together the flour, baking soda, baking powder, and salt. Gradually add dry ingredients to the batter a little at a time, beating over low speed.
Evenly spread the batter into the prepared baking pan. Bake in the preheated oven for 20 minutes, or until edges are golden brown. Remove from the oven and allow to cool completely before frosting.

Easy Buttercream Frosting

Stir all ingredients together until smooth and fluffy. Start by adding 3 tablespoons milk and work up from there until frosting is the desired consistency.
Spread over cooled cookie bars.

Extras

Place m&m’s on top of cookie bars to resemble scales like on a fish and add any color-friendly sprinkles and sugars as desired. Cut into bars and served.

These festive mermaid dessert bars are simple to make, which is why these Mermaid cookie desserts will be a total splash of fun for your mermaid party ideas!

More Delish Cookie Bars!