It might just be a totally dumb question, but is it possible, or would it make the fondant sticky and icky? I'm going to be making MMF, if that makes a difference. If that won't work, will regular liquid color work, like McCormick brand or something? I'm not looking for bright colors, pastels are fine. Would it work if I added extra ps maybe? TIA, kinda desperate here...

Piping gel isn't strong enough color and it would probably just make it a mess.

You can add liquid color as part of the water in the beginning, if you want it all one color.

To add color later, you would have to compensate with more powdered sugar and/or cornstarch.

oh I didn't get a notice that there was a reply. I'm going to make the recipe with fluff, don't want to deal with melting marshmallows. I've made it before but never colored it. I guess I'll try adding liquid color to the fluff in the beginning. thanks for your reply!