I recently made Michele Foster's Fondant and thought I followed the directions perfectly. When I went to use it later, it was a little harder than fondant should be, but not like a rock. I pulled off a small piece to work with and it was crumbling into little pieces. I read Michele's posts to attempt to figure out what was wrong and decided to add glycerin. After adding a lot of glycerin, I was able to pull off my elephant cake. But I tried to use it last night and it is still crumbling.
I have a cake to make this weekend and don't have time to make more. Can I salvage it?
Probably, like 90% of the botched batches out there, you didn't let the liquid come to room temp (like almost cool) before mixing it into the PS. The warmer it is, the more PS it takes on, the longer it takes to get to the consistency she describes. By then, it's too late, and you have what you are describing. You can't take PS out, and adding glycerine only helps so much.