I have to make five colors of fondant tonight. Some of the colors I have in premade Satin Ice fondant but they are too dark for my use. Can I mix a dark blue with white fondant to make a lighter blue or would it be easier to start with the white?

I just mix the colors with the white and that works fine for me. Add a little white at a time getting to the color that you need and then let the mixed fondant sit for a minute. It becomes very soft from all that kneading.

It's just about as easy to knead two colors together as it is to knead color into white fondant, so either way will work, as long as what you want is really a lighter version of the color you have. I don't think navy blue would make light blue if it was mixed with white, for example, because navy is more of a dark gray blue.

Ive had better results mixing two colors together, specially if it's Satin Ice. The pink they have makes a wonderful baby pink when you mix it with white! The only thing is that it just comes in a couple of colors!