Give your next batch of brownies an instant upgrade with this easy brownie frosting! It’s thick, fudgy, and rich, making it the best chocolate frosting for brownies!
Why I Love This Chocolate Frosting for Brownies
- It’s easy: Yes, we are all about the easy here, and this chocolate frosting is simple as can be. If you can make a boxed brownie mix, you can make this brownie frosting recipe.
- It’s delicious on boxed brownie mix or homemade: Speaking of boxed brownie mix! This frosting also gives any boxed mix an upgrade (Ghirardelli triple chocolate brownie mix is my personal fave!), but it’s also perfect with your favorite homemade brownie recipe. You can even use it on my homemade cosmic brownies!
- It’s rich & delicious. So. Good. This brownie frosting is way better than canned store-bought, with a supremely fudgy texture and rich chocolate flavor.
Tips & Ingredient Notes
This is just an overview, click here to jump down to the full recipe card for the recipe amounts and condensed recipe instructions.
- Unsweetened cocoa powder: I use Hershey’s cocoa powder, which will give you that classic chocolate flavor. Just be sure not to use hot cocoa mix, which is something entirely different!
- Butter: I like using unsalted butter for this recipe. This helps you control the level of salt, and therefore the flavor of the brownie icing.
- Powdered sugar: no substitutions can be made here, as we need the fluffy powdered sugar to make the buttercream.
- Vanilla Extract: enriches the flavor but can be omitted in a pinch
- Salt: this enhances the chocolate flavor and helps tone down the sweetness of the powdered sugar
- Milk: we use milk in this recipe to help thin it out; you can use any type of milk or cream
Flavoring Ideas for This Brownie Icing Recipe
Want to add some flavor to your brownie topping? Try these ideas.
- Peanut butter: Add 3 tablespoons of peanut butter. You can also top this peanut butter frosting for brownies with Reese’s pieces or chopped peanut butter cups!
- Mint: Add 1/2 teaspoon of peppermint extract. Top this mint frosting for brownies with crushed peppermint candies!
- Coffee: add 1 teaspoon of espresso powder or substitute the milk for cooled liquid espresso
- Cosmic Brownies: Use this frosting on my homemade cosmic brownies or just use it on a batch of boxes of brownies with rainbow chip sprinkles!
How to Make Chocolate Buttercream Frosting for Brownies:
- Beat 1/2 cup of softened unsalted butter, 2 teaspoons of vanilla extract, and 1/4 teaspoon of salt in a microwave-safe mixing bowl until the mixture is smooth and creamy.
- Reduce the mixer speed to low, then slowly add 1/2 cup of cocoa powder and 2 cups of powdered sugar.
- Stop to scrape down the sides if needed, then add 2 tablespoons of milk and beat on high for a minute or two. At this point, you can add another tablespoon of milk to make it thinner, more powdered sugar to thicken it up, or move onto the next step.
- Heat the frosting in the microwave for 15 to 30 seconds, then stir until smooth.
- Spread it onto a 9×13 pan of brownies.
Tip: Microwaving this fudge frosting for brownies makes it glossier and easy to spread!
Storage & Freezing
Storing: You can cover the bowl (press the plastic wrap directly onto the frosting) and store this brownie frosting in the fridge for up to a week. You’ll need to warm it up in the microwave again & stir it before you use it.
Freezing: Chocolate frosting for brownies can be transferred to a freezer bag or airtight storage container and frozen for up to 2 months. Let it thaw in the refrigerator, then heat it in the microwave before frosting your brownies. You may need to add a splash of milk or whip it in the mixer to help it come back together.
Frequently Asked Questions:
Do I have to refrigerate this frosting?
The high sugar ratio in buttercreams like this makes the milk & butter shelf stable for 1-2 days. If it makes you feel better, store your frosted brownies in the fridge or wait to frost until closer to serving.
Can I make chocolate frosting for brownies without powdered sugar?
You do need some kind of powdered sweetener to make chocolate icing for brownies. If you can’t eat sugar, or you’re avoiding it, you can try a powdered sugar substitute like Swerve instead (I haven’t tested it myself).
How do you make a frosting for brownies that hardens?
This frosting is nice & thick and will firm up in the refrigerator. Although the sugar to milk ratio makes the frosting shelf stable for a few days, store your frosted brownies in the fridge for peace of mind.
How long should you wait to frost brownies?
You should let your brownies cool completely before you frost them. This keeps the frosting from getting greasy and it prevents the brownies from getting crumbs in the frosting.
Chocolate Frosting for Brownies
This is the best frosting for brownies! It's rich, fudgy, and full of chocolate flavor. Best of all, it comes together in minutes!
Makes 1.5 cups frosting, enough to frost 9×13 pan of brownies.
- 1/2 cup unsalted butter (1 stick) softened to room temperature or microwaved for 10 seconds
- 1/2 cup unsweetened cocoa powder I use Hershey's brand
- 2 teaspoons vanilla extract
- 1/4 teaspoon salt
- 2 cups powdered sugar
- 2-3 tablespoons milk
Before you begin! If you make this, will you do me a huge favor and leave a review and rating letting me know how you liked this recipe? This helps my small business thrive so I can continue providing free recipes and high-quality content for you.
In a microwave-safe mixing bowl, beat the softened butter, vanilla extract, and salt on medium-high speed for 1 minute until smooth. Turn the mixer to low speed then slowly add the cocoa powder and powdered sugar. You may need to stop and scrape down the sides. Add 2 tablespoons of milk.
Beat on high for 1-2 minutes until creamy and the frosting is at a good consistency to pipe. If it looks too runny, add more powdered sugar. If it looks too stiff, add another 1-2 tablespoons of milk until you get to the desired consistency.
Place the mixing bowl in the microwave and heat for 15 to 30 seconds, or until glossy, easy to stir and smooth.
Spread the frosting onto a 9×13 pan of brownies.
Although the sugar to milk ratio makes the frosting shelf stable for 1-2 days, you may want to store your frosted brownies in the fridge for peace of mind.
Last Step! Please leave a review and rating letting me know how you liked this recipe! This helps my small business thrive so I can continue providing free recipes and high-quality content for you.
Nutrition is just an estimate and calculated for frosting only; based on 24 servings.