I may have invented something new in the culinary world. Sweet lemon butter to die for! Undoubtedly, somebody has done this before me, but I haven’t seen any mention of it on the forum. So here’s what happened:

1) I screwed up while assembling a wedding cake last month. Most of you know the story. Rebeat some chilled lemon mousseline before it reached room temperature. It was a text book failure—broke down irretrievably. I set it aside and made a new batch. At clean-up time, I put it in the freezer.
2) Took out one of the containers yesterday and thawed it in the fridge overnight.
3) First experiment today, I rebeat a small portion directly from the fridge and used it to frost a small piece of cake. It tasted fine but was slightly mottled in appearance. Not sure if that will show in the photo. But I was thrilled that it came together! What I put into the freezer on August 22nd was a soupy mess of curd and liquid separated.
4) Second experiment tonight, I rebeat a small portion left out until it came to room temp. Voila! Sweet lemon butter. That’s the second photo.

It is so tasty. Still holding its shape, several hours later at room temp. A bit shiny but not mottled. Smooth as…butter! But the taste of lemon buttercream. Not the texture you’d want for a buttercream but…. This would make a superb filling for certain kinds of cake. Sponge especially. Probably great in a jelly roll. Maybe a filling for sandwich-type cookies? I could see it with shortbread! A lovely spread for nut cake slices and short tea biscuits. Oh! a dollop as a kind of hard sauce on top of my grandma’s hot Christmas carrot pudding—the kind made with suet! Who knows what else?

I might have to curdle some MBC on purpose in the future. I checked for sweet lemon butter recipes online, and they don’t sound like they would produce anything nearly as good. So shhhhhhh, let this be our little secret.

The only possible catch is that this mousseline was inadvertently made with one of the extra-rich butters available now. Caused me no end of problems with both the cake and the bc, so you probably don’t want to duplicate that part on purpose. You’d have to experiment to see if you get the same results with a curdled MBC made with regular butter at 80% MF. My guess is that you probably would.

Great report and what better than not wasting anything!  To me, seems that the curdled mbc gathered together at cold temp due to the high fat butter.  Indeed, calling your invention lemon butter is appropiate!

Excellent save!  I’m so glad to hear you didn’t throw the batch away!

Thanks so much for sharing this!  Rose mentions in the new book that the high-fat butters emulsify better than regular, maybe that helped you get such a great “save”.  If anyone is looking for a simple lemon butter, there is a very tasty one included in the Lemon Crepes Suzette recipe in TCB.  I could eat it with a spoon…

Thanks, everyone. Yep, I hate waste of any kind! It will be interesting to see if the same result can be achieved with a failed mousseline made with regular butter. An opportunity may present itself one of these days - you never know. Meanwhile, thanks for the pointer to Rose’s lemon butter sauce, Julie. The Cake Bible seems to me like an inexhaustible gold mine! How blessed we all are to have had Rose come into our lives and our kitchens!

Carolita - 16 September 2009 01:48 PM

How blessed we all are to have had Rose come into our lives and our kitchens!

I couldn’t agree more.
Thank you for posting this. It sounds so delicious.

Great save Carolita! I’ve been making mousseline all this while with 83%MF butter, so it’s great to know that Rose recommends high-fat butter in the new book. Maybe that’s why I’ve never had a problem despite the tropical weather here. And Julie, thanks for pointing out the Lemon Butter in TCB..I never even knew it was there!!
Rose’s ‘presence’ in our lives and kitchens is indeed a blessing.

Shimi, I’ll be interested to see Rose’s comments in the new book on high-fat butter. I checked with her via the blog about my sense that it was the culprit in making my cakes sink in the middle recently. She agreed that the butter I was using, at 82.9% MF, would weaken the cake structure and create that result. She also comments in that blog thread about other applications where using extra-rich butter requires adjustments to your ingredients

I’m so pleased for you that, in your climate, the high-fat butter seems to help your bc. In my experience, that one horrible day in August finalizing the luxury lemon wedding cake, it was a nightmare. I had to keep putting the bc in the fridge every 10 or 15 minutes and rebeat because it would become loose and spongy in no time flat. It was not a particularly hot day. The mix had gone well - no problems with the temp of the syrup, etc. I even added a batch of MBC made with regular butter, so the high fat content would have been diluted somewhat. Yet my mousseline behaved much like Rose’s white choc cream cheese bc. It didn’t pipe well at all! And it was sliding off the cake, when I tried to do touch-ups at the venue. I’ve never had those problems before.

I read about your woes with the lemon mousseline for the wedding cake, as well as the test cakes, and Rose’s reply on the blog…and I was going uh oh in my head. What pitfalls did I unknowingly escape with?? In this case ignorance was bliss I guess. I’ve been lucky (?) so far as have never had a problem with my bc or cakes. The butter I use is Australian, cultured and high-fat.

Maybe there’s a difference between brands? Regardless, I’m so pleased for you that you don’t have those problems. Hooray!

Great save, Carolita!

I have come across one recipe that sounds a little like your “lemon butter,” though it uses whole eggs that are not beaten to become fluffy. It is Pierre Herme’s Lemon Cream as presented in Dorie Greenspan’s “Baking: From My Home to Yours.” Here’s a link to the recipe, plus some hints. I have tried this and it is fabulous! Very buttery—many folks have tried reducing the butter a bit and it is still fabuluous.

http://www.seriouseats.com/recipes/2008/04/lemon-lemon-lemon-cream-recipe.html
http://www.doriegreenspan.com/dorie_greenspan/2008/05/the-most-extrao.html

And I just did the lime-ginger variation, too. Also fabulous.
http://tendercrumb.blogspot.com/2009/08/creamiest-lime-cream-meringue-pie-twd.html

Thanks, Barbara! I’ll look forward to viewing those sites. Time for bed now, though. It’s been quite a day, and I’ve got another one like that tomorrow.