I was thinking of using brown piping gel to achieve the look of coffee or hot chocolate. Does anyone have any other suggestions for either beverage?

Thanks!

Bump. I'd like to know, too!

I think thinned BC or even RI would work. Tinted piping gel would be good for black coffee, but coffee w/ milk or hot chocolate are more opaque.

You can start with any color icing or fondant, then paint a thin coat of piping gel over it. That will "liquefy" it.