When I want people to beg me for a recipe for cake, this is what I make. My creamy, sweet Marshmallow Frosting made with marshmallow fluff and butter is great on top of any type of cake, cookie or cupcake. It comes together in just minutes with a hand mixer.
Yes, this cupcake icing is sticky, but it is so worth it! It has an unforgettable butter flavor that people won't stop talking about. It's the perfect blend of marshmallows and butter, and it belongs on almost everything.
This recipe starts with a jar of marshmallow fluff, which is not the same as marshmallows, by the way! I can barely keep it in my pantry, because I love to use it in so many recipes. If you happen to come across a jar of strawberry fluff, make my strawberry rice krispies treats. If plain is all you can find, don't miss my fruit dip made with fresh strawberries.
Words almost can not express the deliciousness that is this recipe! There is something magical that happens when sweet, sticky marshmallows collie with butter and a big hit of salt. It's salty sweet perfection in a bowl or on a cupcake!
Ways to Use Marshmallow Frosting
- Anytime you make my small batch of chocolate cupcakes, it's worth thinking about this recipe for piling on top. What you see in the photos is my eggless chocolate cupcakes recipe.
- I have it on good authority that kids love it if you smear this between my small batch sugar cookies to make cookie sandwiches.
- If vanilla is more your style, my small batch vanilla cupcakes are great with marshmallow frosting on top. In that case, I add mini marshmallows on top to help show the flavor before eating, otherwise, it looks like a plain vanilla cupcake.
- For any Easter celebration, marshmallows and carrot cake were made for each other. Either in the form of carrot cake cupcakes or a small carrot cake made in a 6-inch cake pan.
- Speaking of a small 6-inch cake pan, you can pipe this into pretty roses for my mini vanilla cake. For Valentine's Day, swap in my mini chocolate cake.
Ok, I trust that you can find many ways to use this delicious marshmallow frosting, so let's talk about the ingredients.
- Butter. This recipe makes enough frosting for 1 dozen cupcakes, so we need one and a half sticks of unsalted butter that has been softened to room temperature. The best way to soften butter is to open the package, slice it into tablespoon-size chunks, and let it rest. When you can easily make a fingerprint in the butter, it's ready to use. However, make sure it's not overly melty.
- Powdered Sugar. Because marshmallow fluff already contains sugar, we just need one cup of powdered sugar.
- Vanilla Extract. An extra dose of vanilla amps up the flavor here.
- Salt. Please don't skip the salt. We need one-half teaspoon of fine sea salt to dissolve in the bowl. It really balances all the sweetness, so please don't skip it. Also, please don't use coarse or large-grained sea salt, as it might not dissolve properly.
- Marshmallow Fluff. One 7-ounce jar of marshmallow fluff in the classic, white plain flavor. If you're lucky enough to find other flavors of it, experiment and enjoy!
In a large bowl, add the butter. Beat with an electric mixer on high speed until light and fluffy, at least 2 minutes. It will go from bright yellow to a more pale yellow color after beating.
Continue beating and add the powdered sugar a little at a time until fully incorporated.
Add the salt and vanilla and beat for another minute to fully dissolve the salt.
Finally, scrape the contents of the marshmallow fluff from the jar into the bowl as best as you can. It’s super sticky!
Beat everything together until nice and fluffy, and the frosting is no longer sticky. It should be fluffy and spreadable.
If your marshmallow frosting is still too sticky or runny, beat it longer! After another 3-4 minutes, if it's still not the right texture, refrigerate it for 30 minutes and beat it again.
Tips and Tricks for Marshmallow Frosting:
If your results are runny, I urge you to just keep mixing. Turn your electric hand mixer to high speed, and keep whipping it until it stiffens up. If that doesn't work, place the bowl in the fridge for 30 minutes, and then beat again. I don't recommend adding more powdered sugar to stiffen it up, as sugar is a liquid ingredient and dissolves and makes things runnier. Using a colder temperature is the best way to achieve great results with any type of frosting that contains butter.
I don't mean to cause such drama in your life, but actual marshmallows and marshmallow fluff are quite different. Marshmallow fluff is not just melted marshmallows, so please don't melt marshmallows to make this recipe. Actual marshmallows have a lot more gelatin in them so that they can hold their shape, so melting them and then blending them just will not work. I'm sorry! But with leftover marshmallow fluff, you can make make my peanut butter marshmallow cookies!
Almost always, leftover food is meant to be stored in the fridge. This is because cold temperatures prevent bacteria growth. So, after making this recipe, store it in the fridge and simply let it rest at room temperature for a few minutes before serving to soften. Any leftovers can go in the freezer for up to 3 months. Defrost overnight on the counter and then re-whip before using.
Because this recipe contains dairy in the form of butter, it is really meant to be stored in the fridge. However, the butter will cause it to harden slightly, so simply remove it from the fridge for about 20 minutes before serving. Let's practice good food safety, ok?
- 1 ½ sticks of unsalted butter
- 1 cup powdered sugar
- 1 teaspoon vanilla extract
- ½ teaspoon fine sea salt
- 7 ounce jar of marshmallow fluff
- In a large bowl, add the butter. Beat with an electric mixer on HIGH speed until light and fluffy, at least 2 minutes. It will go from bright yellow to a more pale yellow after beating.
- Continue beating and add the powdered sugar a little at a time until fully incorporated.
- Add the salt and vanilla and beat for another minute to fully dissolve the salt.
- Finally, scrape the contents of the marshmallow fluff from the jar into the bowl as best as you can. It’s super sticky! Beat everything together until nice and fluffy, and the frosting is no longer sticky. It should be fluffy and spreadable. See tips below if overly sticky or runny.
If it's runny, keep beating. Turn your electric hand mixer to high speed, and keep whipping it until it stiffens up. If that doesn't work, place the bowl in the fridge for 30 minutes, and then beat again. I don't recommend adding more powdered sugar to stiffen it up, as sugar is a liquid ingredient and dissolves and makes things runnier. Temperature change is the best way to achieve results with any type of buttercream.
Amount Per Serving: Calories: 381Total Fat: 23gSaturated Fat: 14gTrans Fat: 0gUnsaturated Fat: 8gCholesterol: 61mgSodium: 206mgCarbohydrates: 45gFiber: 0gSugar: 37gProtein: 1g