I made the Duncan Hines Tres Leches cake. But can't decorate it
I tried making the stabilized whipped cream but I think I overbeat it cuz it turned to soup. Then the cake was too runny to take out of the pan and place on a cakeboard.

Does anyone have a good recipe or tips on how to decorate a Tres Leches cake? Or how to make it less runny?

Thanks in advance!

o hun you didn't
You put the filling on the cake while it was still in the pan? O man if that's the directions they gave you they should be shot. (sorry bout that). Usually if you want to decorate a tres leches cake you can turn it out of the pan before you add the filling. Pipe a dam of your frosting that you are using around the top of the cake and then pour your filling onto the top of the cake. Let it soak in then frost the whole cake. You might not get all the filling into the cake but you can get quite a bit.
I have made the tres leches cake from the recipe here on c.c. and I had loads of the filling mixture left over, (made wonderful coffee creamer though). But I did use ALOT. I even was able to make a layer cake with that recipe (the cake part is quite dry and able to hold quite a bit of the mix).
I hope that I have helped and not confused you further.
Probably what happened is that the DH mix is designed to be served from the pan and not decorated. Except maybe to pipe dollops of whipped cream on each individual serving.