Found it…took me 3 minutes online. I started with powdered sugar topping, then nonmelting powdered sugar, which led me to snow sugar, which led me to this:
Dottie, thank you. I would never have guess from the description of this product that it was the one you had used. This description doesn’t say anything at all about any fat being mixed into the sugar, but I do see from the nutritional content that it does have some. I noted that one of the commenters said that she used it on the Lemon Coolers, which is the cookie I was having trouble with.
I wonder how many porn sites you’d hit if you googled powdered sticky stuff!
The thought makes me shudder.