Last night I attempted to make my second ever batch of SMBC. It was a disaster!! I halved the recipe from Sweetapolita:
5 (fresh) whites, 1.25 c (granulated cane) sugar and 3/4 pound butter (Bluebonnet margarine). I cooked the egg whites and sugar to 140F on my candy thermometer and the whipped the meringue with the whisk attachment until the bowl was room temp (about 11 min). The meringue was thick, fluffy and glossy as the pics showed. Then I added the cubed butter one cube at at time. The butter had been out of the fridge for a little while but was not room temp and was barely soft (I really don't think it was too soft). The icing was looking just like the pics in the post: sort of curdled, which I understand to be pretty normal in the beginning. Everywhere I have read, people say to just add a little more butter and keep beating it, so that is what I did. For almost 20 min! It remained a soupy, thin liquid (but less clumpy). I put it in the fridge for 15 min and tried again but still got the same result. I left it in the fridge overnight and still get the same result after 10 min of beating with the whisk attachment.
Does anyone have an idea what I am doing wrong? Is my SMBC salvageable? Could the fact that I used margarine (Bluebonnet) instead of real butter make a difference? I think margarine has a higher water content so could that be the problem? I use bluebonnet for everything else and have never had any problems. I really think I followed the instructions exactly. I'd love some troubleshooting advice.
Your mistake was using margarine. In some recipes, like cakes, you can substitute, but not in SMBC. Has to be butter. Margarine has too much water, and doesn't return to a solid state like butter. Margarine stays in a soft state, even when refrigerated. I've personally don't use SMBC because it's too finicky to make, and my family finds it too sweet. I use cooked flour icing. No fail, not overly sweet, easy to make, pipes beautifully. And a lot less expensive to make too. With cooked flour icing, you have a choice of using 100% butter or 50/50 butter and shortening. Still tastes great either way.
I have no idea about margarine but this sounds like it could also be temperature. I make IMBC and it seems to emulsify best at 68-73F. I can start with warmer meringue and cooler butter and meet halfway or let both get in the zone before I add butter. Either way a thermometer is really helpful. Since you let the meringue go awhile, and you say the butter was pretty cold, it may have been too cold before you put it in the fridge. Try using a thermometer. I am frustrated by recipes that go on about "just softened" butter and "cool to the touch" bowls, that's hard to get right and it would be better just to invest in a thermometer. The other thing people say is "just keep beating it" but I think the strategy is more about coming to room temperature (in either direction) than agitation. A heat gun is handy.
You could add some chocolate or butter or peanut butter? I had this problem befkre where even 20 minutes in the refrigerator did not fix it until I added my peanut butter where it suddenly whipped into glorious smbc. But you should start with trying to change margarine to butter.
Google Foolproof SMBC on a blog called CakePaperParty.
I agree - do not use margarine in SMBC. It's a completely different structure than standard buttercream. I don't believe its salvageable. I would start over. It's foolproof with a standing mixer and real butter.
You can use 50% butter and 50% vegetable shortening (like Crisco) for better consistency of your SMBC.
Real butter worked perfectly. Thanks so much for the suggestions!
If it is for yourself to eat then I would try saving it by adding icing mixture to it and making it a hybrid ABC/SMBC, the icing sugar should take care of the extra water and adding a little (very little) bit of salt will cut the extra sweetness down.