Tessa’s Recipe Rundown
Taste: These homemade Cosmic Brownies have a much better chocolate flavor than the store-bought ones! No weird artificial flavors here.
Texture: Ultra-rich, fudgy, and chewy. So good.
Ease: Very easy!! Enjoy a batch of these in just over an hour.
Why You’ll Love This Recipe: An easy DIY version of your favorite nostalgic childhood treat.
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These Homemade Cosmic Brownies will evoke all those childhood memories of snacking on those little plastic-wrapped store-bought brownies – but these babies are SO much better!
Real, decadent, and satisfying chocolate, without all the crazy artificial ingredients.
When I was a kid in elementary school, I’d ALWAYS request a Little Debbie brownie as my special treat in my lunch box.
Before Cosmic Brownies, there were only the Little Debbie brownies with the nuts. I would always pick off all the nuts.
I knew I had to make my own version from scratch.
These little brownies are ultra-rich and fudgy, almost like candy. I got as close to the texture of the store-bought kind as I possibly could. I hope you love them as much as I do!
Sprinkle of Science
What are Cosmic Brownies?
Cosmic Brownies, created by snack company Little Debbie, basically summarize a childhood in the 1990s in each bite. They are chewy with a rich, fudgy frosting that’s dotted with rainbow crunch sprinkles. They come individually wrapped and are super sweet and quite artificial tasting.
In creating my copycat version, I opted for a fudgy chocolate ganache topping that delivers a much better burst of chocolate flavor.
Check out the side-by-side below – my homemade version is on the left and the store-bought is on the right:
Ingredient Notes for Success
Butter vs. Oil in Brownies: Which is Better?
Brownies made with butter are fudgier and softer than oil brownies. You’ll find these Cosmic Brownies call for all butter to provide the best flavor and melt-in-your-mouth texture.
Check out my Butter vs. Oil in Baking article for a full breakdown on each of these fats and how they affect tenderness, flavor, and texture in baked goods (and not just brownies).
Cornstarch + Corn Syrup = Secret Ingredients
There is a small amount of both cornstarch and corn syrup in this recipe to help make the brownies super chewy and fudgy.
Feel free to omit the corn syrup or use golden syrup if you prefer, but note that your brownies just won’t quite have that same Cosmic texture. Don’t skip the cornstarch – learn why cornstarch is important in brownie recipes here.
Extra Egg Yolk = Fudgy & Chewy!
You’ll notice in most of my brownie recipes I add an extra egg yolk. This adds fat and protein which translates to rich, fudgy, and chewy brownies.
How to Avoid Dry, Crumbly Cosmic Brownies
The key is to measure your dry ingredients properly. It’s super easy to accidentally add too much flour and cocoa powder – unless you use a digital kitchen scale to ensure 100% accuracy.
If you don’t have a scale, use the spoon and level method for both the flour and cocoa powder to ensure accuracy, and avoid dry, hard, cakey, or crumbly brownies. You can learn more about how to measure ingredients properly here.
The Best Brownie Baking Pan
- I highly recommend using a light-colored metal baking pan. This is my favorite baking pan for brownies, blondies, cheesecake bars, cookie bars, and more.
- Avoid using dark-colored metal pans; the darker the color, the more likely you are to burn the edges or have dry edges.
- Glass or ceramic baking pans will take LONGER to bake these brownies, and the texture may become dense and gummy. Learn more in my Glass vs. Metal Baking Pans article.
How to Cut Brownies Perfectly
Use a large sharp knife and run it under hot water, wiping it off completely between slices.
How to Store
Frosted, sliced brownies can be stored in an airtight container for 3 days at room temperature or for 1 week in the fridge. They are best served chilled, for maximum fudginess.
FAQs
Where to find rainbow candy-coated chocolate?
I used to use Wilton Rainbow Crunch for topping Cosmic Brownies (as seen in the pictures here), but those are increasingly difficult to find. This Baker’s Choice version is available on Amazon, but feel free to use rainbow sprinkles, mini M&Ms, or whatever you like to top these brownies.
Can I skip the corn syrup?
Yes, just not your brownies may not be as chewy. You can use golden syrup or invert syrup, instead.
Can I double this recipe?
Yes, simply double all ingredients and bake in a 9×13-inch metal baking pan, adding 2-3 minutes extra baking time.
Struggling with Flat or Dry Cookies?
My free guide shows you how to fix texture problems and bake cookies you’ll love.
Cosmic Brownies
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Ingredients
For the brownies:
- 10 tablespoons (142 grams) unsalted butter
- 1 cup (200 grams) granulated sugar
- 1/3 cup (67 grams) packed light brown sugar
- 3/4 cup plus 2 tablespoons (88 grams) unsweetened cocoa powder, sifted
- 1/2 teaspoon vanilla extract
- 2 large eggs plus 1 egg yolk
- 1 tablespoon corn syrup
- 2/3 cup (85 grams) all-purpose flour
- 1 tablespoon cornstarch
- 1/4 teaspoon fine sea salt
For the frosting:
- 1/2 cup heavy cream
- 1 1/2 cups (255 grams) semisweet chocolate chips
Rainbow Candy-Coated Chocolate Chips , or mini M&M’s, sprinkles, or other candy, for topping
Instructions
Make the brownies:
- Preheat the oven to 350°F. Line an 8-by-8-inch metal baking pan with parchment or foil and spray with cooking spray.
- In a large microwave-safe bowl, melt the butter for about 90 seconds on high power. Stir in the granulated sugar, brown sugar, and cocoa powder. If still very hot, let cool slightly before adding in the vanilla, eggs, egg yolk, and corn syrup. Stir until very well combined. Add in the flour, cornstarch, and salt and stir until just combined. Batter will be thick. Pour into the prepared pan and bake for 25 minutes. Let cool completely in the pan.
Make the frosting:
- Place the cream in a small microwave-safe bowl and microwave on high for 1 minute. Add in the chocolate chips. Let stand for 3 minutes before stirring until smooth. Pour over the cooled brownies and smooth evenly. Sprinkle with the Rainbow Candy-Coated Chocolate Chips. Refrigerate for 1 to 2 hours, or until the frosting is set, before cutting.
- Brownies can be stored in an airtight container for 3 days at room temperature and for 1 week in the fridge. Brownies are best served chilled.
Recipe Notes
Where to Find Rainbow Candy-Coated Chocolate Chips?
I used to use Wilton Rainbow Crunch for topping Cosmic Brownies, but those are increasingly difficult to find. This Baker’s Choice version is available on Amazon, but feel free to use rainbow sprinkles, mini M&Ms, or whatever you like to top these brownies.
The Ultimate Cookie Handbook
Learn the sweet SCIENCE of cookie baking in a fun, visual way to customize your own recipes frustration-free. Plus, my best 50+ homemade cookies!
More Brownie Recipes:
- Best Chewy Brownies – my most popular recipe!
- Nutella Brownies
- Raspberry Brownie Recipe
- Toffee Brownies
- Malted Brownies
More Copycat Recipes:
This recipe was originally published in 2014 and has been updated with recipe improvements and new photos. Photos by Ashley McLaughlin.
Can I use dark corn syrup? Or another replacement for the light corn syrup? Thanks!
I LOVE it. I have never tried a store bought ,since they don’t sell them in Greece but it’s the best brownie EVER. I have a question I want to make a large batch can I double it and bake in a 9*13in pan? What is your advice?
To me this recipe did not taste like cosmos brownies at all. I was super excited but was just not pleased with it.
This is my first recipe of Tessa’s that I’ve made. I baked them 28 minutes and they turned out gooey , moist and perfect. Thanks Tessa!
These look so good! They would be so fun to make with kids!
These were fantastic! I used Hershey’s Special Dark Cocoa for the brownies and Dark Chocolate Chips for the frosting. Also topped with Reese’s Pieces. Baked in a glass pan with foil. Brownies were perfect at 28 minutes. These were incredibly scrumptious! Will be making these often. A big hit with my boys. Thanks!
This is really gorgeous for everyone
Could I use real maple syrup instead of corn syrup or golden syrup? I use it in other recipes as a substitute as I cannot have corn products. (I would also be substituting arrowroot for the cornstarch)
I haven’t tried! Let us know how it goes if you do 🙂
What kind of baking pan do you use for these? I have just about every material known to man and I try to follow recipes exactly.
I almost always bake brownies in a metal pan – specifically aluminized steel – because it conducts heat more efficiently than glass or ceramic. Hope that helps!
Your topic is very great and useful for us…thank you
Super yummy and a huge hit!!
I was wondering if you measure each tbsp individually which seems like too much work! Using a 1/2 cup plus 2 tbsp would be easier if you didn’t have a kitchen scale. I consider homemade brownies to be the ultimate comparison (rather than store bought or box mixes) as that is what I grew up with. These sound yummy. I’ve just discovered your site via a link on brown-Eyed Baker. Your how-to guides look fabulous. I have, until now, limited myself to 2 food blogs but I think I’m going to add you to my list.