Who has a good chocolate icing recipe?

[Nousernameforme]

Following on, well sort of, from a thread with a greedy DH.
Someone linked to Micheal Rosens Chocolate cake poem
www.poemhunter.com/poem/chocolate-cake/

I am making a chocolate cake for DD to commiserate or congratulate her results on Thursday. Well it's any excuse for cake really but hey.
I am looking for the type of chocolate icing that isn't ganache and isn't buttercream.

I remember it from my childhood (80's if that makes a difference) and it was spread thin kind and had the little crackle skin type top you get on water icing. It always went on top of the cake whilst buttercream went in the middle.

Does anyone have a clue what I am on about

Nobody has one?

I just use icing sugar, a small lump of butter, and a bit of boiling water. Or is that what you mean by "water icing"?

Sorry - plus cocoa, obviously, for chocolate icing!

Whipped double cream and melted dark chocolate. 100ml of cream and 100 grams of chocolate.

Do you mean something like this?

www.thespruceeats.com/easy-chocolate-glaze-for-cakes-desserts-3053469

@thehongalahadthreepwood thank you so much just made up a tester of it and it's near perfect. My water icing is always just water and icing. My only thing I think I need to recreate it is Cadbury drinking chocolate rather than cocoa