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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 wonโt stop talking about. Itโs 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, donโt 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. Itโs salty sweet perfection in a bowl or on a cupcake!

Marshmallow Frosting Recipe Ingredients
Ok, I trust that you can find many ways to use this delicious marshmallow frosting, so letโs 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, itโs ready to use. However, make sure itโs 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 donโt 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 donโt skip it. Also, please donโt 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 youโre lucky enough to find other flavors of it, experiment and enjoy!
How to Make Marshmallow Frosting


- 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.ย
- Continue beating and add the powdered sugar a little at a time until fully incorporated.ย


- 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. Itโs 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 itโs still not the right texture, refrigerate it for 30 minutes and beat it again.

How to Store Marshmallow Cake Frosting
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.
Does marshmallow frosting need to be refrigerated?
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. Letโs practice good food safety, ok?
Marshmallow Cream Frosting FAQs
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 doesnโt work, place the bowl in the fridge for 30 minutes, and then beat again. I donโt 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.
So, marshmallow fluff isnโt just a jar of melted marshmallows. It contains slightly more corn syrup to make it smoother and spreadable. If you want to create marshmallow fluff from marshmallows, melt the marshmallows over very low heat. When the marshmallows are melting and still a bit lumpy, stir in light corn syrup slowly until the mixture fully melts and becomes white and creamy. Remove from heat and let cool before using in your recipe.
Grainy marshmallow frosting occurs when you make the marshmallow fluff from scratch, with egg whites and granulated sugar. The graininess is actual grains of sugar that did not dissolve in the heating process. However, my recipe for marshmallow frosting starts with a jar of marshmallow fluff to prevent this!
Ways to use Marshmallow Fluff Frosting
- Anytime you make my small batch of chocolate cupcakes, itโs 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 Valentineโs Day, swap in my mini chocolate cake.
Marshmallow Fluff Frosting
Fluffy, creamy marshmallow frosting made with marshmallow fluff. Recipe makes enough to frost 1 dozen cupcakes.
Ingredients
- 1 1/2 sticks of unsalted butter
- 1 cup powdered sugar
- 1 teaspoon vanilla extract
- 1/2 teaspoon fine sea salt
- 7 ounce jar of marshmallow fluff
Instructions
- 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. Itโs 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.
Notes
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.
Nutrition Information:
Yield:
6Serving Size:
1Amount Per Serving: Calories: 381Total Fat: 23gSaturated Fat: 14gTrans Fat: 0gUnsaturated Fat: 8gCholesterol: 61mgSodium: 206mgCarbohydrates: 45gFiber: 0gSugar: 37gProtein: 1g














Hello! Sounds like a frosting my daughter would love! Iโm wondering if youโve ever tried tinting it for decorating? Thank you!
Hi! Excited to try this recipe, but do you think you could include how many cups/grams are in โsticksโ of butter? I am Canadian and had no idea this was an American unit of measurement.
Happy Holidays!
Hi, Kim,
Your question was so long ago โ maybe youโve gotten your answer by now(?). One stick of butter is 8 tablespoons, or 1/2 cup, or 4 ounces.
There are online measuring charts available for converting units of measurement like cups, teaspoons, tablespoons, etc.
Hope this helps.
*From a fellow Kim*
Wow! The marshmallow frosting is next level and a fabulous change to buttercream. Please could you update with metric weight for all ingredients. Iโm so keen to make a batch. Thank you. ๐ฅฐ๐๐ง
Hi. Can I use this frosting to put into a layer cake. Not sure if it would melt if I am putting it in between the cake layers. Thanks.
You can, keep it cold and store in the fridge:)
Would this work well inside or covering an ice cream cake?