I've been using Satin Ice fondant but didn't have any on hand so I decided to make MMF. I've made it in the past and had no problems. Today it's giving me ulcers though. It just has no stretchiness to it. It just rips - it seems almost more like playdough than fondant. Is there something I can add to it that can save it? I need this cake done today so if there's anyone that can help - PLEASE!!! I will repay you in smiley faces and good vibes!

Okay, now I just read somewhere that the MMF has to sit overnight in order for it to become stretchy. True? It's been awhile since I've made it but I don't remember letting it rest before using it before and having it still be stretchy. Yikes. Maybe this cake will be covered in only buttercream after all...

Sounds like you put too much icing sugar in it. I would put it back in the microwave for 20 - 30 seconds to get the marshmallows soft, then knead it again with a lot of crisco. HOpe it works.

I very rarely let my MMF sit overnight. It's usually nice and stretchy right from the get go. In fact, I only let it rest if I want it to be a little more stiff for decorations instead of covering it. I agree with hvanaalst. Try warming it in the microwave and knead it with crisco, though i would start slowly with the crisco.

What if I softened up more marshmallows and added them? Do you think that would help?

More marshmallows would probably help, you can also try warming up a few tbs of corn syrup and kneading that in along with a tbs of shortening. Another option is to work in some white modeling chocolate. It's almost always possible to save MMF!

Let it rest. If you can't wait overnight, just stick it in the refrigerator for about an hour and it will be so much easier to work with.

To me it sounds like you didn't add enough liquid. Maybe a little vanilla? The shortening might help too.

Good luck!

Oh, and I'm not sure what you're using it for, but you could add a little tylose.

Okay, so I tried a few things. I wrapped it in plastic wrap and let it sit a couple of hours, then I microwaved it, kneaded in a little shortening and a little glycerin. Doing those few things made it a little more pliable, but not much. I was able to pick it up and get it on the cake but had a big rip when I did. I decided to leave it on the cake rather than pulling off and having to start over. I used the infamous "cakers creative coverup" maneuver. So it's not done yet but I'll post a photo when it is. Definitely less powdered sugar next time. Thanks to all for so much help! Here's the payment I promised:
And the good vibes are in the airwaves coming your way!