Last month for my birthday I made a delicious lemon cake and I made a new (to me) buttercream that was like a meringue, but then you add a bunch of butter and voila, buttercream! I was so delicious - not super sweet and it was a dream to spread on. It was so awesome, I decided to make it again.

Just like last time, I made it ahead and refrigerated it. It looked great when I scraped it into the dish and put it in the fridge. Just like last time, I took it out and let it come to room temperature. Just like last time, I popped it in the mixer to fluff it up a bit before spreading it.

Unlike last time, it turned into a crumbly mess with a pool of liquid in the bottom of the bowl. Yikes!!

So I tossed it, ran to the store and got two more packs of butter, made the whole thing over again and this time, right out of the gate, it was a crumbly mess with a pool of liquid. Yuck! I popped it in the fridge and then took it out awhile later and tried to hand beat it. It's better and I wasn't going to make another batch to I just iced the cake with it, but it was like spreading gloopy butter and it's all weird and oily looking. What a mess. What happened!?

Oh, too bad you tossed it. The temperature was wrong. You have to bring the buttercream to room temp before you re-whip it. And, when you made it the second time your butter was probably too cold, it also has to be room temp to emulsify with the meringue, otherwise it will separate as happened to you, sorry! The merigue buttercreams are a dream to work with but definitely take some getting used too. If it happens again, you can take some of the buttercream out and melt it in the microwave, then throw this into the mixer with the cold stuff and it should come back together. Don't give up it is wonderful stuff!

If it had a curdled look to it, you need to keep whipping, it will come together, just be patient!

You had a broken buttercream! This is a chance to see the coolest thing that you'll see happen in the kitchen (yes, I'm an icing geek.) Like Rexy said, keep beating it on high and the heat from the bowl and the whip will eventually make the icing come together again. You can speed up the process by wrapping a hot dish towel around the bowl while the beating is going on. At some point the temperature of the butter will warm up enough that the whole curdly mess will suddenly turn into a bee-oo-tiful bowl of smooth icing. It's so cool to watch...I make my kids come over the watch when the icing breaks, but they're not as interested as I am, ha ha!

The opposite thing can happen, too, which is where you put the butter into the icing when it isn't cool enough, and it ends up being soupy. You can bring it back from this but it takes a little longer and involves stuffing a lot of bags of ice and frozen vegetables up under the mixer bowl while the whip is turning. (You can also refrigerate the bowl until it cools down, but that takes longer.)

LOL, I agree with costumeczar...I love watching my broken IMBC come back together. It's like magic! I especially love it because in the recipe I use (from the Cake Bible) it specifically says if it breaks down it will be irreparable. I'm like: Oh yeah? Repair THIS, baby!!

Lately my butter has been too warm before adding so it's been the soupy kind of broken. I find that popping it in the fridge for 15 minutes works better than frozen veggies/ice packs - maybe my frozen veggies aren't cold enough because they just defrost before my icing comes back together

I actually use a similar buttercream and my recipe says not to refridge....but maybe it's different. But you are right...it is my favorite buttercream !

I agree with everyone else on this...it can take a while - like 10 min or so, but your buttercream will come back together to this amazing buttercream!

I however made a rookie mistake the second time I made it. I am so new to baking and everything cake that I thought you could use meringue powder in place of egg whites. I followed the Wilton recipe on the side of the meringue powder can and got this amazing meringue all whipped up and then once I added the butter, I got this incredible mess - a soupy weird mess that NEVER came together. So, I asked a pastry chef and she laughed and said nope - you have to use real egg whites!! Meringue powder doesn't work as soon as you add a protein...so, no cutting corners for me! I went back to egg whites and whalllllah - perfect IMBC!!!

Lesson learned I guess!

I made Alton Brown's recipe and it never ever came together. I whipped that thing forever, literally. I stuck it in the fridge and did it again the next day--never came to.

I have yet to try it again.

I'm just going to add my two cents...I only use Italian Merengue Butter Cream...and yes, it is very temperature sensitive...but once you get the hang of it...there is nothing like it (I use confectioners sugar/butter/shortening for Piping roses...and only for piping roses).

I love my SMBC, when it works!!! Through trial and error, I have learned most of the tips mentioned above.

My process during the summer in my non-air conditioned cake room has been:

1. Cook egg whites, sugar and salt while hand whisking constantly. When mixture becomes smooth and soupy (120F), start beating with a hand mixer over the simmering water until it comes to temp.

2. Pour into KA bowl and beat in stand mixer for 12 minutes.

3. Take 1lb block of butter out of fridge AFTER 12 minutes of beating. Cut 1/2 lb of butter into TBSP pieces and add to mixture on med speed. Beat for 1 minute while cutting the other 1/2 lb of butter. **Adding hard cold butter prevents a soupy mess that would need to be refrigerated.

4. Add second 1/2 lb slowly, tbsp by tbsp every 10 seconds for last 1/4 lb, then it should start transforming into curd-like state and resume to creamy goodness. Hold ice packs and frozen veggies on sides of KA bowl (while beating) after all butter is added to start the curdling stage.

I am so glad I've read this! I really want to try one. Can you leave a cake iced in meringue bc out of the fridge?

Ah, thanks!

Tell me how these work with fondant cakes? How long can they be out of the refrigerator???

MBC icings and fondant are really not a concern, as long as you chill the cake rock-hard before applying the fondant. You have to work fast to smooth the fondant on before the icing starts to soften if you use a "normal" layer of icing like I do, but that's true with any icing under fondant (i.e. if you want to use a lot of icing, you've got to get that cake nice and cold otherwise the fondant will just squish the icing around.) But once the fondant is on, as you know it kind of dries out a bit and essentially it supports itself. It's kind of like a shell over your cake. So even if you let your MBC cake sit out for 4 hours, you'll be fine. I personally don't leave my IMBC cakes out except for display and serving. Although that can sometimes mean 3-8 hours, I still refrigerate to store. I've found that Michele Foster's fondant recipe refrigerates perfectly. I've had mixed results with MMF, although MacsMom has a MMF recipe which withstands refrigeration just fine. So do commercial fondants btw.

My first attempt at SMBC was off. It was tasty and smooth but to soft. I could only get a layer ont he cake and then I had to pop it back in the fridge. When I cut it up to eat the icing was melting off the cake like soup before we could finish our 1" slices. Any guesses as to what I might not have done right?
I followed the Well Dressed Cake SMBC. Though I have a hand mixer.

I have to admit, I had a hard time with SMBC too. First off I always scrambled the eggs, no matter how careful I was. The closest thing I had to a successful batch was still too soft. I always use IMBC instead, with pasteurized whites for safety. I love the Cake Bible's Mousseline Buttercream recipe, although I up the vanilla to 1 TBSP or more.

What is the trick to getting these type of BC firm and stable?
IMBC is more complicated to make and I worry about the raw eggs too. But does it make a firmer BC?
I regular hi-rat/butter/PS BC is just soo sweet and I was hoping to find something more rich and less sweet.
I LOVED the lightness and richness of the SMBC.

Ya know my whole problem is that I can not use whipped/heavy cream in my icing because of milk allergies. So the hi-rat/butter/PS BC is missing the balance of rich savory fat to counter the sweet.

Ceshell do you pasteurize your own egg whites by bringing them to 160' and then cooling them to beat the meringue.

Oh and my "butter" is a vegan soy cold expeller pressed spread that is just like butter, but does have a slightly higher water content. So that could account for some of this also. I need a magic wand over here!

Maybe I need some kind of stabilizer... what should I use? Vegetable gum, soy lecithin? Maybe the emulsifier would help too. I guess I have some experimenting to do.

sadsmile, I just use pasteurized ew from the carton - any brand but AllWhites seems to work for me. Powdered ew work too. Some theories state that the 248º sugar syrup cooks the ew to 160 but I'm not going to trust that. I don't know how to answer your butter question though - I would think that it surely could have an effect, unless you don't see it giving you any grief in any other uses. You could try using some hi-rat instead of your vegan butter - I've seen several people here sub out a bit of shortening for the butter in order to stabilize their mbc.

Personall I find IMBC way easier to make than SMBC but I think that is because for me, I just cannot get the hang of heating the ew without scrambling them. No matter what I do! Technically futzing with a sugar syrup separate from beating the ew...well it IS more complicated...but still simple if that makes any sense. I can't be sure (because I've never gotten SMBC to cooperate) but from what I've read IMBC is a teeny, tiny bit stabler than SMBC. Meaning, like by one or two degrees. Mine is always firm and holds up terrifically under fondant (once chilled) - just did Cinderella's carriage - a ball pan with IMBC and fondant?! No problems

If it were me I'd blame it on the vegan butter and pop in some shortening to see if that will help!

Thanks Ceshell! That is something I am going to have to try! I'll let ya know.

Ceshell...TOTALLY goin off topic right now because I have to say again how awesomely awesome that GNR cake is that you made! Anyone that hasn't seen it, go check it out in her pics!

*BLUSH*