Cook’s Illustrated note:

Frosting can be made with milk, semisweet, or bittersweet chocolate. Cool chocolate between 85-100 degrees before adding it to the butter mixture. The frosting can be made 3 hours in advance.

For longer storage, refrigerate the frosting, covered, and let it stand at room temperature for 1 hour before using.

20 TBS (2 1/2 sticks or about 10 oz) unsalted butter, softened
4 oz. confectioner’s sugar
3/4 cup dutch-processed cocoa
pinch of fine table salt
3/4 cup light corn syrup or (Lyles Golden Refiner’s Syrup and 1 TBS of water)—I prefer the Lyles Golden Syrup)
1 tsp vanilla extract
8 oz chocolate, melted and cooled

In a food processor, process butter, sugar, cocoa, and salt until smooth, about 30 seconds.

Scrape the bowl as needed.

Add the syrup and vanilla and process until just combined, about 5-10 seconds.

Scrape down the bowl, and then add the chocolate and pulse until smooth and creamy, about 10-15 seconds.

Frosting can be used immediately or held.

Roxanne’s Note:

Cook’s Illustrated doesn’t give a plain vanilla version, but I have successfully made one by replacing the cocoa powder with 1/2 cup more of confectioner’s sugar, increasing the butter by 1 TBS, and adding more vanilla extract (or whatever other extract or flavoring that you want).

The big key to this recipe is using a light hand with the processor and not over mixing it. I have also made this in a mixer, but I just watched the butter very carefully; you don’t want to whip too much air into the butter. The whole point of the processor method is being able to mix it up quickly.

Personally, I prefer to make this over whipped ganache, as ganache can be finicky and it can easily curdle from overwhipping

I have made this frosting twice, and I love it. However, I much prefer it made with bitter or semisweet chocolate over the recommended milk chocolate in CI’s magazine.  The milk version was overly sweet to me, and not much chocolate punch.  I did it both ways - food processor and kitchen aid mixer. The only reason I prefer the KA mixer method is that it’s more difficult to get all the frosting off the blade and out of the bowl using the FP.  But the FP method sure is quick and easy.

Roxanne, I have to ask, was the vanilla version icky sweet?  I can just feel my teeth hurting with all that sugar and corn syrup.  In the chocolate version, at least the sweetness is tempered by the unsweetened cocoa powder.

MrsM

The vanilla version was pretty sweet, but I did that on purpose as I was pairing it with a sour cream, bittersweet chocolate cake that had barely any sugar in it at all. I just piped rosettes of butter cream on each slice of cake. I used this instead of whipped cream because it wasn’t going to be refrigerated.

For a less sweet version, you would have to play around with it a bit. What I would do to begin with is use the original recipe as directed, just omit the cocoa powder, but keep the butter and powdered sugar (maybe cut the powdered sugar down by 3-4 TBS or so) the same. When you get to the point of adding the syrup, add just half of the amount called for, then taste. If it’s not sweet enough to your liking, add the syrup in small additions until it’s where you want it to be. I also added more salt than just a pinch to the vanilla version (about 1/4 tsp); it seemed to tame the sweetness a bit.

All in all, I really like this frosting. It’s an excellent alternative to egg based buttercreams (which I love, but they are not very practical to use on a cake that is going to be sitting out all day long).

Roxanne

MrsM - 30 March 2008 07:54 PM

I have made this frosting twice, and I love it. However, I much prefer it made with bitter or semisweet chocolate over the recommended milk chocolate in CI’s magazine.  The milk version was overly sweet to me, and not much chocolate punch.  I did it both ways - food processor and kitchen aid mixer. The only reason I prefer the KA mixer method is that it’s more difficult to get all the frosting off the blade and out of the bowl using the FP.  But the FP method sure is quick and easy.

Roxanne, I have to ask, was the vanilla version icky sweet?  I can just feel my teeth hurting with all that sugar and corn syrup.  In the chocolate version, at least the sweetness is tempered by the unsweetened cocoa powder.

MrsM

Roxanne - I chanced upon your post in another thread and was led to this, in my search for a smooth vegan buttercream.  Having cut my teeth on Rose’s buttercreams, when it came to producing vegan cupcakes (which I will be doing regularly) for my son’s group of friends (one of whom has egg, dairy and nut allergies) I have been unable to reconcile myself to having to produce vegan versions of American buttercream - the type which uses confectioner’s sugar.  While both the kids and adults appear to have no problems and indeed like the vegan cupcakes with the vegan buttercream, knowing what REAL buttercream (especially mousseline) is like, it pains me to have to serve the gritty stuff.  That’s right, I can’t get the powdered-sugar icing to be smooth and silky.

It appears from your post that this is what the CI recipe was developed to do… get around the grittiness.  What I wanted to know was, does it really?  I know there is no comparison to Rose’s buttercreams in terms of texture, but I guess I really want to know HOW close it comes, and does it at least produce a somewhat silky product? 

I have been on a mission for the last few months searching for a way to veganise mousseline or at least make a silky vegan buttercream (that is pipeable - yes I know I ask a lot), but it seems even if one can use margarine and non-trans-fat shortening (there’s no getting around it!!!) there’s no substitute for the egg component in Rose’s recipes.  Unless there’s a way to make italian meringue without egg whites, LOL.