Hi, I hope it is not too late but I had this same problem yesterday and when I did a search I found out that you can add Hersheys special dark cocoa powder to the buttercream. It worked wonderfully and still tasted great. Without it I could not achieve a dark brown.
momofil...not sure where you are at this point with this particular cake, but I feel so bad for you. I think you should look into Americolor icing colors for the next time...you won't have problems like this in the future.
Are you sure the icing is not dark enough? Icings usually darken as they sit/dry...put some on a spoon and use the hairdryer to help it along to see if that will get you closer to where you need to be for this cake.
What are ya makin'?
You add a touch of black.
Or try mixing red or orange with a touch of black....(I'd actually do this in a separate bowl first).
Or lastly you could try mixing orange and blue icing to get brown...
Good luck!!! Let us know how it goes!!!
-Michelle
Quote by @%username% on %date%
%body%