I was pretty thrilled when one of my NZ based manufacturers told me, he could produce a double milled icing sugar specifically formulated for donut glazes. It's double milled to ensure it's nice and smooth. The small amount of maltodextrin added ensures the icing has a wonderful shine and doesn't snap or crack.
I made two types of icing recently. Maple, using the lorann maple flavouring which was super tasty
And for the kids strawberry using the Gobake flavacol. Which they declared AMAZING!
This new icing comes in 1kg packs, at the great price of just 5.95