Until this last time my homemade MMF didn't tear, but it did have poke marks all over it.  Then I made chocolate MMF that has lite corn syrup in it, and it didn't have poke marks, so I thought it was because of the corn syrup.  So I added corn syrup to my most recent batch of MMF thinking it would make the MMF more elastic and eliminate poke marks.  

When I was rolling out the MMF, it looked perfect, no poke marks, nice and smooth.  But as soon as I tried to pick it up it immediately tore, big tears.  I couldn't use it. The more I kneaded it, the worse it got! 

Did I add too much corn syrup? I didn't adjust the recipe any other way.  So my recipe was:

16oz. mini marshmallows

2 Tbsp. water

7c. powdered sugar

plus the added 2 Tbsp. corn syrup

Should I have used more powdered sugar? The chocolate MMF has more powder because of the cocoa.  Is this the difference?  I saved the MMF.  Can I knead in more powdered sugar to fix it, or is there anything I can do to fix it?

Or is it the colder, drier weather?  

It looked great when rolling, but not usable!

Thanks in advance! 

I don't use MMF, but with any fondant, it will tear if you are rolling it too thin.  Also, if the piece is large, either roll it around your rolling pin to lift and unroll on your cake, or roll it on a mat, then lift the entire mat and invert the fondant onto the cake.  This will help keep it from tearing under its own weight.  HTH.

I use 1 T of vegetable glycerin instead of corn syrup. Everything else you use is exactly what I use. 

What is vegetable glycerin?

I don't think it was too thin.  I rolled it to the same thickness and did everything exactly the same as usual, the only difference was adding the corn syrup.  Did I add too much?  Maybe just 1 Tbsp would be better since clevershepig only uses 1 Tbsp of veg glycerin.

I buy glycerin at whole foods. It is used as a beauty product to soften skin. I think it's what gives the fondant its elasticity. There are different varieties, but not all are edible. The brand I buy is by Now solutions. It is clearly marked food safe. I have also seen a different brand at WalMart, but it's not consistently stocked. I hope that helps!

Thanks for the glycerin advice!

Does anyone know if or how I can fix the batch of MMF I already made?  I'd rather fix it, and not have to make a new one.

Thanks again.

AWilton also makes a glycerine. You may want to test the glycerine in a small amount of your already made fondant tosee if it repairs it. Best wishes!

I add 4-6 oz of melted white candy melts to my melted marshmallows when making MMF. Makes it less stretchy.
 

I already have glucose, would that help fix my MMF?  I'll buy glycerin if I need to, but thought I'd ask before going to Michaels.

I don't think it will have the same effect on the fondant as glycerin. Glucose, I believe, is similar to a thick corn syrup.

You did everything correctly.  The only thing I can think of is that it's either too thin (which you said it's not) or you didn't roll it out (mix the powdered sugar in) enough.  I've used MMF for years and one thing it never does it tear - EVER.  Do me a favor the next time and use Kraft marshmallows instead of a store brand and use good Domino's powdered sugar.  Maybe the corn starch in the powdered sugar and dusted onto your mini marshmallows (you are using the mini's right?) is compromising your recipe.  What I would do now is to grease my hands generously with Crisco, microwave the batch of fondant and work the Crisco into the batch, roll out then use a couple clear mats to lift the fondant down onto your cake - or a rolling pin.  This is a real cake you're covering, right, not a square dummy with sharp edges?

DeniseNH: I was thinking that maybe I didn't use enough powdered sugar, which might be necessary since I added the corn syrup.  I don't use corn starch at all.  I tried kneading in more Crisco last time, but it tore more easily each time I tried to cover the cake, so I don't know if it was Crisco making it worse.  Would adding powdered sugar help?  And it is a real, round cake.  

I also have never had my MMF tear, that's why I didn't know what to do.  Maybe I should leave out the corn syrup and go back to my original recipe, but then there's the poke marks again!

You can try adding more powdered sugar but there's something wrong with your ingredients.  I too add a couple tablespoons full of corn syrup to my MMF - instead of water while microwaving it so that's not the problem.  Did your powdered sugar come right out of a bag from the store or did you empty it into another container then grab the flour instead of powdered sugar?  Please get better ingredients (name brand powdered sugar and name-brand mini marshmallows).  You colored it, correct?  Did you use a liquid color or the gel colors?  If you used liquid - you would have needed to incorporate a lot more powdered sugar..................to counter that, I would melt a couple cups of mini marshmallows and add it to the old colored fondant.  Looks like it's lost its stretch.  Hey, another idea, did you mistakenly use a 10 oz. bag of marshmallows instead of the standard large bag (16 oz.)  that might be the problem.  Check your marshmallow bag sizes.

That's good advice about the color. When I make deeper toned fondant, it almost always tears. Red is especially bad. 

I think I figured out what was wrong with my recipe.  The mini marshmallows tasted fine, but I checked the other bag that I bought at the same time and they had expired 6 months ago!  Either that or it was too dry.Although I used water to melt them and mixed in the corn syrup after. I definitely used powdered sugar.  I used Americolor gel color.  I was going for a marble look, but in the end it was all blue because I had to keep kneading it.  The more I kneaded it the worse it got, so maybe it was the color.  I'll try adding marshmallows.  

I didn't try to fix it yet, but I did make a new batch with new marshmallows and instead of using water I used the corn syrup when melting.  I kneaded it for almost 15 minutes before rolling it out.  The edges were splitting, normally that would be a problem, but it was the first time I used THE MAT! and it was awesome!  It looked so smooth on the cake (and no poke marks) even though I did it in a hurry.  Hopefully The Mat will also help the blue MMF turn out better and keep from ripping.