Thanks but no, I haven’t changed a thing. The food coloring was all purchased in the past 6-8 months. I’ve tried using Americolor soft paste and Chefmaster liquigel and both result in the same issue. And I can’t work the streaks out no matter how much I stir, my cookies look terrible with streaks and blotches of white all throughout.
If you've changed nothing and it all worked well before, it's tough to know how to guide you. The likely culprit would be something you changed, but . . . I know that, for the most stable results with coloring, I always mix the coloring into thick icing and then gradually thin it to the consistency I need. I find I get more spotting and such if I start with a loose icing and then color it. Not sure why that would be, but it seems to be the case for me. Other than that, all I can suggest is trying newer coloring (check the expiration date on those bottles). But, honestly, the color doesn't look too bad from the photos.