Frosting. Specifically chocolate. (Remember Sara Lee's?)

I am trying to figure out what recipe will create the only chocolate frosting I like.

If you remember Sara Lee chocolate cake from the 80’s and earlier, THAT.

If you know Nemo cake, THAT.

It’s dark in appearance, but doesn’t taste “dark” (semisweet, I guess) It is not ganache, I know that for sure. It’s some kind of buttercream, I am 99% certain, but which, and how?

The taste is very rich, but the texture is very light and buttery (meaning it’s almost guaranteed not to be “american” buttercream: i.e. confectioners sugar and butter in some combination). The texture tells me it’s probably a Swiss meringue buttercream, especially since there is a marked difference between chilled/cool/warm (too warm and the frosting melts) but I can’t for the life of me figure out how to get that dark appearance and rich flavor. Most recipes end up being light in appearance and flavor, and when I try to just boost the chocolate, it ends up too “dark” in flavor. I don’t want it fudgy, thick or grainy, of course. Like satin…

So…unsweetened chocolate? Cocoa? A combo? Semisweet? bittersweet? Dutched? Swiss meringue, French? (whites vs. yolks) It’s maddening!

Do you know what I mean, and do you have a recipe?

(incidentally, Sara Lee evidently still makes that cake, but only for “food service” - damn shame. Also a shame they discontinued the chocolate pound cake, that stuff was amazing, especially slightly warmed with butter… sounds crazy until you consider the fact that frosting is butter, only with a boatload of sugar, so butter alone really isn’t that outrageous.)

I don’t have it handy, but the recipe for chocolate frosting that is on the back of the Hershey’s Cocoa box makes the best chocolate frosting I’ve ever made, and it sounds like your description.

Just passing thru; here’s a pic of the back of the box. (Scroll down)

If it’s the Sarah Lee cake I’m thinking of, isn’t the frosting a chocolate mousse? I can buy it frozen in many places, (UK), so I’ve never tried to recreate it.
If it’s just the frosting you’re after, try out different mousses.
It is a light as a feather though, cake and frosting, so I’m pretty sure it’s so full of artificial yumminess ,that’s it’s going to be impossible to exactly reproduce.
Maybe a whipped cream mousse on a chocolate angel cake?