This easy chocolate fudge frosting is perfect on cakes, cupcakes, brownies, and more!
- 3 1/2 cups powdered sugar
- 3/4 cup cocoa powder
- pinch of kosher salt
- 1/2 cup melted butter
- 1/3 cup hot water (you may not need it all)
- Mix powdered sugar, cocoa powder, and a pinch of salt together in a large mixing bowl.
- Stir in the melted butter. It will quickly clump up into a crumbly, sandy mixture - that’s what we want!
- Add hot water to powdered sugar mixture a Tablespoon at a time, stirring well between each addition (you likely won't need all the water!) The frosting will slowly start to come together. Continue stirring, adding water as needed, until the frosting is quite thick: It should have the consistency of warm fudge or a thick pudding. (It won’t look or feel like the traditional buttercream or whipped frostings we’re often used to!)
- Spread frosting over your prepared cake or cupcakes. Work quickly here - the frosting will set and harden as it cools. Let it sit at room temperature for an hour or so to fully set, then serve and enjoy!
How hot should my water be? The water here should be quite hot - nearly boiling - for best results. We usually heat water to the highest setting in an electric tea kettle, but you can also heat it in a small saucepan on the stovetop or (carefully) in the microwave. If you don’t have the time or equipment to heat water this way, you can use water straight from the tap on its hottest setting - it won’t keep the frosting soft for quite as long, but it will still work!
How much frosting does this make? As written, this recipe makes enough for a thin layer of frosting on one large sheet cake, a very thick layer of frosting on an 8-inch square cake, or a generous dollop of frosting on 10-15 cupcakes.
Fudge frosting will seize and harden as it cools, so work quickly to frost your cake. If the frosting is too thin (this often happens when too much hot water is added) add extra powdered sugar or let it cool on the counter for a few minutes to thicken it up. If frosting is too thick, stir in an extra splash of hot water or zap it in the microwave (using a microwave-safe bowl) for 5-second intervals to loosen it.
This frosting works best on cupcakes and sheet cakes. As it cools, the frosting will become more difficult to spread, so use it on low-maintenance cake styles like a sheet cake or cupcakes (rather than a layer cake) for best results. Because the consistency changes as it cools, we don't recommend piping this frosting with a pastry bag.
Frosting will last up to 4 days in an airtight container on the counter once it’s applied to your cake or cupcakes. After a few days, the frosting will lose some of its texture and start to release some of its moisture, which can make the cake below a little bit sticky. For best results, frost your cake as soon as you mix the frosting, and eat it within a day or two!
For a dairy free and vegan frosting, use melted coconut oil in place of the melted butter here.
Keywords: frosting, dessert, chocolate, cake