Can I add lemon juice to an all butter buttercream recipe or will it react badly with the butter? I'm making a practice cake today and wanted to try a lemon buttercream but I'm not sure if it will work.

I have done this and it worked out just fine (I also used some of the zest), but if you're worried they do make a lemon extract you could try.

Thanks. I was hoping to do it without a trip to the store since we don't live in town. I'll give it a try and see if it works.