I have a cake order and they want a black or very dark blue background. I know there is no-taste red, is there also no-taste black? I'm not sure if there are icing colors around here besides Wilton brands...
Any tips or hints on how to achieve black or very dark blue buttercream with the same great taste as white??
Personally your best bet would be to use chocolate icing. Dark chocolate if you can (buy the dutch processed dark cocoa) then add the black to it. Also americolor gel colors work great. You can find americolor in many many online shops. They are only about $1 each. If you add black to white icing you are likely to be running around with stained lips and teeth.
I have made a cake with quite a bit of black (using chocolate icing) and no one had stained teeth and it didnt taste bitter at all.