A lighter American buttercream (aka Sweet Cream Frosting)

My Sweet Cream Frosting has a unique light, yet creamy texture. It contains less fat than heavy cream, which is possible via a combination of my mixing technique and emulsifying ingredients. Using butter, milk, sugar, and buttermilk powder gives this frosting a lightly tangy flavor reminiscent of vanilla ice cream with a fantastic and stable texture for frosting cakes and piping atop cupcakes.

This is my second iteration of an American-style buttercream. The parent frosting recipe is American Buttercream, which has characteristics of being a little on the sweeter side, easy to make, and combining powdered sugar with butter.

How does this frosting contain less fat?

First, to preface, when I talk about fat content, it’s not from a nutrition or health perspective. You’re definitely on the wrong page for that stuff. I tend to look at things from a biochemical lens, and when I mention low fat, I’m talking about how that affects the functionality of the frosting, such as texture, stability, and taste perception. 

Fats (or lipids) play a special role in frostings and baked goods. In frostings, it has lots to do with temperature and pressure stability, as they are pretty sturdy molecules. Regarding texture, sometimes a high fat content can be undesirable. It can feel dense or greasy or just overall too heavy. 

And as far as I know, there has yet to be a frosting that is stable without the use of a high ratio of fat. 

To illustrate this a little further, here is a graph of frostings I’ve covered and their relative fat content:

Heavy cream starts off with a fat content of 36% typically, and used in frosting, the fat content can go down to around 32%. I can’t include it in this graph here because it’s not technically a buttercream emulsion and contains a bunch of air, which contributes to its texture. But it’s such a familiar frosting for bakers that I like to think about its fat content when comparing frostings.

Now typically, when there’s less fat in frosting, there’s less stability. But I seem to have found a good breaking point with a fat content between 25% supplemented with additional emulsifiers. 

My emulsion in the buttercream was stable enough to hold up a large 8-inch layer cake, frost beautifully on the sides, and pipe tall swirls atop cupcakes.

How long can sweet cream frosting be left out at room temperature?

I would treat this frosting similar to one that contains cream cheese. And it’s not because of stability issues (like the melting that can occur with whipped cream frostings) but more because it does contain a higher ratio of water. Although, it also contains a good amount of butter and sugar, which are safe at room temperature. 

So given those details, if you want to be super cautious, refrigerate within 2 hours after being in room temperature. For me, I’m comfortable with leaving this cake out in my house for 4-5 hours. Overnight, I will place the cake in the fridge. 

What ingredients do you need for this Sweet Cream Frosting?

Unsalted butter is the primary source of fat in this recipe. The fats as well as milk-derived proteins serve as emulsifiers, or molecules that hold fat and water-based ingredients together in a stable way. The butter also has a bit of water contained within, and that’s going to help dissolve the sugar.  I always use unsalted butter in my frosting recipes as salted butter can be overly salty, particularly in a recipe such as this one where lots of butter is being used.

Sweet Cream Buttermilk Powder is a fine cream or yellow powder.  When butter is churned, the liquid that runs off is sweet cream buttermilk. This is different than liquid cultured buttermilk that you may find in the refrigerated dairy section. That type of buttermilk is low-fat milk that has been inoculated with live cultures, which then ferments the lactose in the milk, creating lactic acid. This gives cultured buttermilk that tanginess and sour buttery flavor.

Here’s a little graphic that summarizes their differences. I see that many recipes and websites (including mine before I researched this) states that these two are the same. Chemically speaking, they have different molecular compositions and pH's, so unless the recipe specifically says so, I would not substitute one for another.

Not all buttermilk powders are the same. I’ve tested a few major brands during my experiments, and by far my favorite is Bob’s Red Mill Sweet Cream Buttermilk powder. It’s got the lightest color and most balanced and beautiful creamy-tangy flavor. I can buy it in my local grocery store, but you can also order it on Amazon, here

My second favorite is Judee’s. Saco brand, which can be found in most big grocery stores is an interesting product because it’s a combination of both sweet cream and cultured buttermilks. (BTW, I think the reason they do this is to increase the acidity of the powder so that it CAN be interchangeable with liquid cultured buttermilk, since that's the flavor that most Americans associate with buttermilk.) I’ve tested Saco with this recipe and it works, though it will have a more pronounced tangy flavor that using a straight up sweet cream powder. 

Whole (4% fat) milk adds water to help dissolve the sugar. It also contributes milkfat and milk proteins, which act as emulsifiers and hold the buttercream together. I’ve experimented with different fat-content milks and whenever I used skim milk (containing no milkfat) the emulsion would fall apart unless I added more buttermilk powder to compensate. So this recipe is specifically formulated to use whole milk, containing around 4% milkfat.

Powdered sugar is the sweetener for this buttercream. It’s a finely granulated sugar with a bit of cornstarch added to prevent caking. I like using powdered sugar in this recipe because it dissolves more readily during the mixing process, creating both a sugar syrup and emulsion simultaneously. Be sure to use a high quality sugar, and I’ll remind you about that in the recipe card.

Fine salt and vanilla extract are optional and added at the end of the buttercream process to enhance the flavor. I prefer this buttercream with a good pinch of salt but no vanilla extract. I find this combo enhances the sweet cream dairy flavor without overpowering it.

Step-by-Step

Please note that you do need a stand mixer to make this frosting. The speed and power is required to homogenize the ingredients so that it forms a buttercream.

This recipe here is based on my Sugarologie method for frostings, where we make a sugar syrup (usually by heating liquid and sugar) and emulsifying it into butter. And although that method is still one of my favorites, it can be challenging and time-consuming. So I worked through many experiments in trying to simplify the process. This one here combines both the syrup making and emulsifying in one straightforward process. 

Step 1: Whip the butter and buttermilk powder.

Remove the butter from the fridge to warm up for about 15 minutes, then cut into chunks. Add to your stand mixer bowl with the sweet cream buttermilk powder (1a) and with  whisk attachment, beat on high speed for 3 minutes (1b). It should be grainy from the powder, yet lighter in texture and slightly paler (1c). 

Step 2: Add milk #1.

In the recipe below, you’ll see that I’ve labeled the milk and powdered sugar #1 and #2. Making this buttercream successfully depends on adding the right amount of ingredients at the right time and mixing them in gradually before moving on to the next step. I split the amounts for us to prevent adding too much of one ingredient at one time, which can cause the buttercream to break. 

Add the cold whole milk #1 in at least 4 additions (2a), mixing in thoroughly, and mix for an entire minute on high speed (2b). At the end of this step, butter mixture should look like this (2c).

To check if the milk has been properly emulsified, you should watch my video below. Un-emulsified buttercream looks like what I call the “washing machine.” The butter is in slippery chunks that slide around the bowl, like clothes inside a washing machine. Once the milk fully integrates within the butter, it will “catch” the side of the bowl, smooth out, thicken, and look like a normal frosting. 

Step 3: Add powdered sugar #1.

The powdered sugar also has to be added in increments. Using a one cup scoop, add approximately one cup of powdered sugar to the butter mixture (3a). Mix until you see no traces of powdered sugar, then add another scoop. Repeat this until all the sugar has been added, then mix on high speed for one whole minute (3b). 

⚠️ CHECKPOINT:

I’ve added a checkpoint here to assess whether or not the initial emulsion is successfully made. I find that if you make it to this point, it’s harder to mess up with the second addition of ingredients.

So make sure that your buttercream looks like this (3c):

  • Creamy smooth
  • Slightly yellow
  • No curdling or soupiness
  • When picked up with a spatula, it does not drip off easily
  • No milk leaking or powdered sugar streaks throughout

If your frosting looks curdled, your buttercream is not emulsified and  it means your butter is too cold. Keep mixing on high speed until it comes together. 

If your frosting looks soupy, your buttercream may be emulsified, but your butterfat is too soft to continue. Place the bowl with the buttercream inside into your fridge for about 5-10 minutes, just enough to put a slight chill on the bowl. Then place it back on the stand mixer, and mix until it thickens and comes together. 

Step 4: Add milk #2. 

Just as in step 2, add the second portion of cold whole milk in at least 4 additions (4a), mixing thoroughly after each addition. The frosting will be lighter in texture, like this (4b).

Step 5: Add powdered sugar #2.

Taste the buttercream. For me, this is perfect sweetness. This powdered sugar is optional if you want, so add in a little at a time, tasting until you like the sweetness. Don’t add more than indicated in the recipe though, or the buttercream might break. You can also add the salt and vanilla in this step.

Step 6: Adjust for color and texture of the frosting.

This frosting is naturally cream colored. Add a speck of purple food coloring to remove the yellow undertones (6a). 

Switch to the paddle attachment and mix for at least a couple of minutes to smooth it all out. It’s now ready to use (6b).

Use my recipe below or visit my Cakeculator for different frosting amounts:

Almost all of my frostings can be found in my cakeculator, which allows you to customize your frosting flavors and amounts based on the cake you're baking. The  frosting recipe below makes 1 or 3 cups, but if you need another quantity, go to my Cakeculator here and choose "Sweet Cream Frosting".

IMPORTANT NOTE: You can perfectly replicate all my cake and frosting recipes using gram measurements. Weighing is the most accurate way to bake and I use it exclusively.

For American bakers who prefer it, I have converted grams to estimated volumes (cups, teaspoons, etc.). These are not as accurate and may have awkward proportions. 

This is the OXO scale I use on a daily basis. If you’re interested in other tools I use for my baking, I’ve compiled a list here.

Hi! I'm Adriana.

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