Use this rich butterscotch-flavored frosting to decorate Martha's spectacular Brown-Sugar Layer Cake or any dessert you please.



Ingredient Checklist


Instructions Checklist
  • Combine 1 1/4 cups sugar and the water in a medium saucepan. Bring to a boil, stirring to dissolve sugar. Brush down sides of pan with a damp pastry brush, and cook, without stirring, until dark amber. Remove from heat, and gradually stir in cream until completely smooth.

  • Whisk together remaining sugar and the egg whites in the bowl of a mixer set over a pot of simmering water. Whisk until sugar dissolves and mixture is warm. Transfer bowl to a stand mixer fitted with the whisk attachment, and whisk on medium-high speed until fluffy and cool and stiff peaks form, about 10 minutes. Add butter, 2 tablespoons at a time, whisking well after each addition. Whisk in vanilla. Slowly pour in caramel with mixer on medium speed, and whisk until completely incorporated. Continue to whisk until smooth, about 3 minutes. Use immediately, or transfer to an airtight container and refrigerate up to 3 days. Before using, bring to room temperature, and beat until smooth.

Cook's Notes

Frosting can be frozen for up to one month.

Reviews (12)

172 Ratings
  • 5 star values: 21
  • 4 star values: 24
  • 3 star values: 87
  • 2 star values: 33
  • 1 star values: 7
Rating: 5 stars
If you know basic ITALIAN MERINGUE BUTTERCREAM (IMB) it’s easy. I made this recipe and it turned out perfect! 1-1/4 sugar and water cooked until ember color remove from heat add heavy cream, this part is your caramel. This has to cool before you add to the buttercream. In a double boiler, egg white and the remaining cup of sugar.( if you have a kitchen aid mixer use the bowl it will be easier. Or use any bowl you’ll make the buttercream with) the point of the double boiler is to melt the sugar with the egg whites, also to pasturize the egg whites if using raw egg whites. I use my hands for this method(gloves of cause) so I can feel when the sugar is melted and also know when the egg is getting too hot, it takes 1-2min for the sugar and egg white to warm up, then immediately attach the whip and whisk until stiff peak meringue forms, it takes about 10 min. Add the butter, I switch to the paddle attachment at this point and paddle for 3-5min. That’s it, Ione Italian meringue it’s not too sweet. Plus the brown sugar cake is sweet enough.
Rating: Unrated
Yes, it is supposed to be white sugar. How do you turn water and white sugar to an amber color? SCIENCE. (The culinary term is caramelization, and pretty much ALL caramel starts out as white sugar. See also
Rating: Unrated
Are you suppose to use brown sugar or white granulated sugar in this frosting recipe? How do you turn water and white sugar dark amber????
Rating: Unrated
Sorry but for some of you who couldn't do this recipe, you didn't follow directions. You melt the sugar and eggs together using a double boiler method. You have to stand over it and mix for a bit until the sugar dissolves. Then you mix it up in a mixer until it forms stiff peaks and is cool. Finally, you add the butter when it is cool. You don't add butter to anything hot, obviously it will make the butter melt. It will break as the other poster said and then it comes together to be fluffy.
Rating: Unrated
I just want to echo what donz1234 said. There is nothing wrong with the recipe directions. Just google “swiss meringue buttercream“ and you will see that the directions for any type of swiss meringue buttercream are the same. SMB is more buttery and less sweet than American buttercream. Make sure you beat the egg whites until the bowl feels cool. When you add the butter, it may get soupy. Just keep beating; it will come back together, but sometimes it takes a while.
Rating: Unrated
This is a great recipe. When you make the buttercream you must be patient. It ALWAYS breaks when you add the butter. Keep will come together in the end! the egg white should not take 45 minutes. All I can think is that you actually cooked the whites too long causing them to no longer whip. The whites and the sugar are being MELTED together in the pan above hot water. Just until the sugar doesn't feel grainy.
Rating: Unrated
DO NOT MAKE THIS RECIPE. Everything about this recipe is WRONG. Thank goodness I decided to make the frosting a day in advance, now I can make a real frosting tomorrow. It took 45 minutes to get firm peaks on those egg whites. And not stirring the caramel as it cooks? What? If you follow the directions and whisk butter into your eggwhites you end up with egg white soup. I knew it wasn't right but went through with the directions anyway, and now I need to repurchase new ingredients. HUGE WASTE!!!
Rating: Unrated
The cake was good but the frosting must be a misprint!!!! Even though I felt the directions were wrong I followed because "How can MS have printed this so wrong?" The butter should be mixed into the melted sugar NOT the egg whites! What a waste of money!#%%^&**!! Eggs and Butter are not cheap! Not to mention the time. BLEECK!
Rating: 2 stars
Ok, I absolutely ADORE everything of Martha's, but the butter in this recipe was a little overwhelming. My stomach hurt just trying it. I was trying these out for my son's first birthday in a couple weeks and am so glad I did this trial run. LOVE the brown sugar cake, but I cut out holes in the center of my cupcakes and added pumkin butter. I'm doing a cream cheese frosting instead.
Rating: Unrated
My icing came out very runny. If it were the icing I normally make, I would thicken it with confectioners sugar. How do I thicken this? It tastes good, but I'm afraid it's just going to run off the layers as I stack them.
Rating: 2 stars
LittleLL...the caramel they refer to is what you make by heating the water and sugar in first step of recipe.
Rating: Unrated
The instructions said to add caramel but I do not see caramel in the ingredients list. Am I reading this wrong?