I've made a lot of MMF this past month and have tinted it both ways.
It shouldn't be hard to knead the coloring into the fondant. If you're finding it takes too much muscle, try microwaving the fondant (5-10 seconds at a time) until it is soft enough to knead easily.
I found it hard to tint too. I suggest coloring very small amounts at a time, then joining all the small amounts to one large amount.
I color mine before adding the pwd sugar.
Debbie
Debbie, that's a good idea ... as long as you are makeing it all the same color, right?
Hello Ladies,
I have a question about MMF.....I would like to make this MMF but after reading some of the other posting about it burning up their KA's I am concerned. When you all make you MMF do you make small batches? I have the 250 KA and I was wondering how to successfully make the MMF without harming my KA. TTATUMMMM you said you have made several batches and I was wondering if you could give me any advice. After you melt the MM and place it in the KA bowl. Is that when you put on your dough hook and add the powdered sugar? Is in like making B/C adding the PS a little at a time? I know I have alot of questions but this looked like a great time to ask. Now I also know when you add the tint. Thanks in advance for all of you all help!!!!!!
Kim
I make it all by hand. I'm too afraid to risk ruining my KA, or shortening it's life.
Plus it's a great upper body workout!
I make it by hand as well. The microwave method should work if you are having a hard time kneading in the color. Good luck!
I add color when I add the melted marshmallows to the powdered sugar in my KA. It works great! 
I had problems with it in my smaller KA, but it's a breeze in the larger one! 
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