This may just be my new favorite frosting recipe!
This silky smooth and lightly sweet frosting is perfect swirled atop cupcakes or as the finish to a layer cake. It would also make the perfect filling for whoopie pies or cookie sandwiches.
The recipe for this heavenly frosting starts just like an American buttercream, with softened butter and confectioners sugar beat until smooth in your mixer. Next comes some marshmallow fluff which gives the frosting more structure. Marshmallow cream is similar to Swiss meringue or a 7-minute frosting; it is a shelf stable meringue. So it is the perfect way to add bulk to a frosting as opposed to adding more powdered sugar.
Finally there is the sour cream, the real star of this simple recipe. When I began making this recipe I would use heavy cream as the sole liquid in this frosting. One day I reached for some sour cream to see how the tang would fit into the overall flavor. Simple perfection! If you don’t have sour cream on hand, plain yogurt or greek yogurt can be substituted. Any of these ingredients will add flavor to this frosting by offsetting the sweetness of the sugar.
If you follow through to my Pumpkin Spice cake recipe you will see how I used this frosting to finish a ‘nearly naked cake.’ This trendy frosting technique is basically a neat crumb coat, with bits of cake showing through a thin layer of frosting. This recipe works will with this technique since the frosting spreads so smoothly and doesn’t drag across the cake.
- 1 pound unsalted butter, softened
- 1 pound 10X confectioners sugar, sifted
- 6 ounces marshmallow fluff (about 1 cup)
- 2 ounces full fat sour cream (1/4 cup)
- 1 Tablespoon vanilla extract
- 1 pinch salt
- 3-4 Tablespoons heavy cream
- In the bowl of your stand mixer beat the softened butter for 1-2 minutes until it is creamy
- Add the confectioners sugar and blend on low to combine. Raise the mixer to medium speed and beat for about 1 minute to ensure that there are no lumps of sugar
- Scrape your mixer bowl and beater then add the marshmallow fluff, sour cream, vanilla and salt
- Beat the frosting for about one minute then add half of the cream, blending on low to combine
- Check the frosting consistency, if you'd like it a bit thinner add a touch of the remaining cream
- Give the bowl one final scrape then beat the frosting on medium speed for 4-5 minutes