Black Icing Tip

I always add Hersey's Cocoa powder to any icing before going black. You can not get a ture shade of black from a white icing. This may answer that question of black icing colors being ashy or charcoal.

Try working with paste color. Example, Wilton and CK (Country Kitchen) are two companies that make excellent products for coloring icing.
Click Here for the Wilton Icing Colors
These colors will not change the consistence of your icing. They are also designed to be more concentrated. When working with rolled fondant, liquid food color will make the fondant very sticky and hard to work with. When working with royal icing liquid food color will thin the icing and your designs will not keep their shape.

I have found working with intense buttercream icing colors like black or vibrant colors like reds, blues, greens, etc. they do stain people's mouths. Rolled fondant tends to not stain when they eat it. This may be for two reasons. First, most people don't eat rolled fondant. They simply peel it off and there is white buttercream under the fondant. The second reason is fondant holds the color in the icing. It may be the gelatin in the fondant that causes this. You can eat a slice or two of cake covered in the black fondant and not end up with a colored mouth.

Hope these tips will help when it comes time to color your icing black.