Super quick Brownie Frosting comes together in less than five minutes with only four ingredients. It is super thick, and the perfect frosting for brownies!

I love a good homemade brownie recipe - they are rich, fudgy, and super easy to make. I am married to someone who thinks that adding a simple chocolate icing onto basically anything will make it better - especially to my fudgy brownies.
In our house, we call this brownie frosting 'shitty chocolate icing' - as in, the super quick, thick, chocolate icing that our Mums used to make as kids.
It's just the best - comes together in five minutes, and goes well on everything. Rich has been asking me to put in on the blog for years now, and now I have finally found an appropriate name for it, here we are - the perfect chocolate frosting for brownies.
This easy brownie icing is everything you need for that perfect, thick, crusty icing that brings back an instant hit of nostalgia. It's not super smooth - it sets with a delicate crust, and is just the best thing ever.
I love using this recipe to make frosted brownies - I also use a slightly thinner version on my cosmic brownie recipe, but it is not just an icing for brownies - you could also use it to finish off my easy banana bread, or as a simple finish to my chocolate chip cookie bars. It would also work great as an alternative frosting on my Oreo Brownies.
Ingredients in Brownie Frosting
The ingredients list for this Brownie Frosting is super simple - it comes together all in one bowl, and is ready to use immediately.
- Powdered sugar - The base of this brownie frosting recipe. Make sure that it is sifted to remove any lumps.
- Cocoa powder - I use dutch process cocoa powder to make my frosting for brownies, but you can use regular unsweetened cocoa powder too if you like. Make sure it is also well sifted.
- Butter - If you use salted butter, skip the salt in the recipe, otherwise add in a teeny pinch of salt to help bring out the chocolate flavor.
- Boiling water. This brings the brownie frosting together and helps to melt the butter, giving a smooth texture, and making it super easy to spread on your brownies.
How to make the best frosting for brownies
This brownie frosting recipe is super quick and needs to be used immediately as it is a crusting frosting, so make it once your chocolate brownies are either at room temperature or chilled, depending on how you like to serve them.
- Combine all the ingredients except for the boiling water in a heat safe bowl. Because we are using grams to make this recipe, you can place the bowl with the ingredients in it directly onto the scale and measure the boiling water straight into the bowl.
- Add the boiling water, and mix to combine with a spatula - it may look like there is not enough water, but just be patient and keep mixing. It will come together.
- Make sure you have mixed until the frosting is homogenous and all the pieces of butter have melted - switch to a whisk if needed to get any lumps out.
- There you have it - the perfect frosting for brownies! Use immediately on your cooled or chilled brownie.
How to get clean slices on a brownie
Here are a few top tips to make sure you get a perfect cut on your brownie:
- Make sure the brownies are properly chilled. I like to make sure that both the brownie and the chocolate frosting are set. If you don't like cold brownies, you can leave them out after you cut them and they will come back to room temperature.
- Use a super sharp knife. This is important for getting a clean cut on anything.
- Cut in one motion - I use a knife with a large blade and push down evenly rather than levering the knife down.
- Wipe the blade between cuts. I don't use a warmed blade, but if needed I do rinse it and dry well between cuts.
Frequently Asked Questions
What tools and equipment do you use?
You can find a full list of the tools and equipment I use on my products page
How do you store brownie frosting?
This brownie frosting needs to be used straight away as it will crust up (which is delicious btw), so use it immediately then store the brownies in the fridge or at room temperature in an airtight container depending on your brownie preference. I am team cold brownies, you do you here.
How long does brownie frosting take to set?
Either you can set this brownie frosting at room temperature, or you can pop it in the fridge. It will get a crust on it quite quickly, but will take 30 minutes or so to set in the fridge, and a little longer at room temperature.
For more brownie recipes, check out:
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Answers to your baking questions
Over the years, many of you have asked me questions about:
- baking in grams
- adjusting oven temperatures
- what kind of salt to use
- and many more!
I've curated and answered them all for your easy reference in this frequently asked questions post!
Super Quick Thick Brownie Frosting
- Prep Time: 5 minutes
- Total Time: 5 minutes
- Yield: 16 servings 1x
- Category: Frosting
- Method: One Bowl
- Cuisine: American
Description
Super quick Brownie Frosting comes together in less than five minutes with only four ingredients. It is super thick, and the perfect frosting for brownies!
Ingredients
- 190g powdered sugar, sifted
- 20g cocoa, sifted
- Pinch of salt
- 45g unsalted butter, at room temperature, cut into small pieces
- 25g freshly boiled water (weigh after boiling)
Instructions
- Combine the powdered sugar, cocoa, and salt in a medium bowl, then add the butter and mix until it is coated. Add the boiling water, and mix with a spatula until the butter is incorporated and the mixture is homogenous.
- Switch to a whisk if needed to get any lumps or remaining pieces of butter.
- Use immediately - this is a crusting frosting so it does not store well and needs to be used straight away.
Keywords: Brownie Frosting, chocolate frosting, brownie icing
Comments
so yum!
★★★★★
I love this frosting! It comes together so quickly and tastes great on everything!
★★★★★
Such an easy, quick and delicious recipe! I used it on the banana sheet cake - perfect!
★★★★★
Delicious! Was the perfect topping for our homemade brownies!
★★★★★
So good! This reminds me so much of the icing my mum used to make when we were growing up (in Aus). I used it to ice a small batch of owl cupcakes for Halloween and it was so easy and super delicious.
★★★★★
Paired this frosting with the fudgy brownies and it was delicious! Both recipes were super easy!
★★★★★
So easy to make and a great addition to brownies. You will never have unfrosted brownies again after giving this a try!
★★★★★
Yum! Easy, tasty, quick. What’s not to love?
So great to have this in my back pocket. I used it for a last-minute chocolate cake.
★★★★★
So good!!
★★★★★
Delicious and SO EASY! The perfect late night recipe to top some basic brownies to really elevate everything. Will lean on this recipe often!
★★★★★
I love this frosting! It’s so easy, dairy free, and reminds me of the chocolate frosting they put on the chocolate peanut butter bars in elementary school. 🤤 I made it in my kitchen aid and it worked out just fine, no need to use the whisk attachment.
★★★★★
Literally the fastest and tastiest frosting there is. Brings me back to school sheet cake which was my favorite. Super easy to make too!
★★★★★
Holy cow. So, first off, I am super particular about a good fudgy frosting. I usually only use my mother’s recipe which probably came from her moth. But, Erin has never let me down, so I tried this tonight for her basic brownie recipe. I am in love with this frosting! It is SO easy and amazingly good! I cannot wait to share these brownies with family this weekend-they will be a hit! Also, the frosting does set fast so make sure you are quick with a spreader! I put some sprinkles on mine and I almost wasn’t fast enough. Five stars-can’t wait to show these off!
★★★★★
I made a batch of boxed brownies that turned out too cakey and dry. So I quickly whipped up this frosting to put on top, and it SAVED THE DAY! I had so many compliments on my baking “fail.” Also, discovering that chilled brownies are superior has legit changed my life. What would I do without Cloudy Kitchen?!
★★★★★
Used this on the Erin's sugar cookie bars and honestly what a delight. It also worked out because I had miscalculated how much butter was actually in my fridge.