I am making a very large batch of cookies for a fundraising event. They will be iced with green RI and then a small design piped on top of them in black. I did a trial using RI for both colours however 12 hours later the black icing has run into the green. Any ideas on how I can avoid this happening?

If the green was to be fully set when I pipe the black will this help?

Is there a better icing I could use for the piping maybe?

Thanks

Whenever I am working with black or dark colors I put in some meringue powder. It helps it set faster without the running colors. Just something I do...hope it helps.

Yes, you need to let the green set completely before applying the black. Let it dry over night and it should be fine. Good luck!

Oh, what brand of coloring are you using? I find that americolor doesn't bleed as much as Wilton. Something to consider.

I am using Wilton colour. I am in NZ so don't think we have Americolor brand available here?

I was just using an egg white and icing sugar mix for the piping. I will look into meringue powder and see where I can get it...

Thanks for the suggestions

I have managed to source an egg white substitute Actiwhite which will hopefully work in the same way as meringue powder.

Thank you so much for your help