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When making deep colors, such as black, brown, or red use Wilton paste food colors in larger amounts than normal. Deep colors are recommended for accent colors only.
When icing is colored deep red, a bitter aftertaste may be detected. Red No-Taste should be used when a large portion of red coloring is used on the cake.
When making black icing, start with your favorite chocolate icing – this doesn't require as much icing color.