AI am not getting a super clear pic of the image from my iPad but that doesn't look like RI to me. I think it's a fondant covered cookie and the look is probably from a texture mat/pin.
AYou could probably get a similar look with a toothpick or impression tool, maybe even crumpled foil. I'm not sure about using RI though, the effect will be different.
Clever suggestions - thanks so much!