Copycat Cosmic Brownie Cookies (With Cake Mix)

Thanks to a boxed cake mix these chocolate Cosmic Brownie Cookies are out of this world easy! The best fudgy chocolate frosted cookies with colorful rainbow chips. Everything you love about your favorite store-bought brownies you ate as a kid, in an irresistible copycat cookie!

We love the convenience of using a cake mix and still cranking out homemade flavor. Have you tried our dynamic-duo Peanut Butter Chocolate Chip Cake Mix Cookies, festive Peppermint Cake Mix Cookies w/Buttercream, or classic Cake Batter Puppy Chow Snack Mix.

What Is A Cosmic Brownie Cookie?

A cosmic brownie cookie is a chewy brownie topped with a thick layer of chocolate frosting and rainbow candy-coated chips. They were first made famous by the Little Debbie Company in 1999 and served as individually wrapped brownie bars.

Why Are They Called Copycat Recipes?

Any brownie labeled “cosmic” is inherently a copycat recipe since Little Debbie’s Cosmic® Brownies are the original fudgy brownie treat and registered trademark. While Little Debbie may have started the enduring craze for this beloved brownie dessert, decades later, the Crumbl Cookie franchise has taken up the banner with their Crumbl copycat Cosmic Brownie Cookies.

Why Are They Called “Cosmic” Brownies?

The “out-of-this-world” snack cake was created because of the popular cosmic bowling trend in the 1990s, featuring colorful glow-in-the-dark bowling pins, balls, lighted lanes, and fun music. The bright and “colorful candy-coated chocolate pieces” and the cosmic-inspired packaging get their signature look from this enduring family pastime.

Why We Love Homemade Cosmic Brownie Cookies

Prepare to embark on a delightful cosmic journey with our cake mix cosmic brownie cookies! Here are six irresistible reasons you’ll fall in love with these cookies:

• Cosmic brownie cookies are a fantastic go-to for a charming and delicious homemade treat.
• A mix of soft, fudgy centers and satisfyingly crispy cookie edges offer the best of both worlds in every bite.
• Rich, homemade chocolate frosting with real cocoa takes this brookie recipe to a whole new level of decadence.
• Vibrant rainbow chips add the signature pop of color to cosmic brownie cookies.
• Customize homemade cosmic brownies with different flavors of cake mix, candy sprinkles, or nuts.
• Visually appealing and oh, so delicious! Share at work, sell at bake sales, or invite someone over for coffee just because!

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Ingredients For Cosmic Brownie Cookies

Packed with rich chocolate flavor and chewy texture, topped with colorful candy sprinkles for a fun and nostalgic touch, these super easy cake mix cookies are made with just 4 ingredients! (Ok, that is a slight of words since we’re making yummy homemade chocolate frosting, but those are simple pantry staples too.)

For specific amounts, please refer to the printable recipe card at the bottom of the post.

How To Make Cosmic Brownie Cookies

Fudgy centers, crisp edges, and rich chocolate frosting crowned with cute cosmic candy toppings are your reward when you whip up a batch of these copycat cookies! Prep your baking sheet, heat up your oven, and get ready to be thrilled to the moon and back with cosmic brownie cookies!

When you are making this recipe, you’ll want to use the full recipe at the bottom of the page.

1. Mix the 4 cookie ingredients just until fully incorporated. Stir in chocolate chips, then chill the dough for 10-15 minutes.
2. Use a cookie scoop to place even-sized dough balls on the cookie sheet.
3. Bake cookies for 8-10 minutes (don’t overbake); cool on the pan for 5 minutes, then transfer to a wire cooling rack.

Fudgy Frosted Layer:

Of course, cookies must cool completely before frosting. The chocolate frosting will set quickly, so do them one at a time; frost and add sprinkles.

1. Make the frosting by simply combining all of the frosting ingredients until smooth. 
2. Frost the top and add the cosmic brownie sprinkles to each cookie. 
3. Save some for others to enjoy!

Recipe Notes And Tips

• You don’t want to preheat your oven until just before you are ready to pull the chilled cookie batter out of the fridge and make the brownie balls, especially if you have the rapid heating option with your oven.
• Use a good quality chocolate cake mix. The better the cake mix, the better the brownie cookies will taste. 
• Remember, overmixing the batter will make the cookies tough, so let’s not do that! 
• Chilling the dough before baking is important because it helps the brookies retain their thick, fudgy texture and prevents them from spreading and becoming too thin.
• Do not overbake cosmic brownies. Bake until the edges are set, and the centers are still slightly soft. The cookies will continue to cook as they cool on the baking sheet. 
• Let the cookies cool completely before frosting or decorating so the chocolate topping doesn’t melt or slide off!
• This fudgy chocolate frosting sets quickly, so frost one cosmic brownie cookie at a time, adding the sprinkles immediately so they will all adhere to the fudge icing

Storage

Frosted brownie cookies will last up to 5 days in an airtight container in the fridge or for 3 months in the freezer.

What Flavor Of Chocolate Cake Mix Do I Need For Brownie Cookies?

The type of chocolate you prefer in your brownies is the flavor cake mix you should use for brownie cookies. Personally, I like a deep rich chocolate, so I usually reach for  Duncan Hines Dark Chocolate Fudge Cake Mix. If Devil’s Food or German Chocolate is your love language, then use it!