Sugarflair Spectral Food Colouring Paste - Royal Blue - 400g This bulk pack of Royal Blue food colouring paste is suitable to colour any type of icing - sugarpaste, flowerpaste, royal icing, buttercream and cake mixes etc. All these colours are highly concentrated and will darken on drying.  When mixing into sugarpaste, use sparingly to achieve a pastel shade, but add more to give a strong, vibrant colour - the consistency will not change too much!   If used for painting onto sugarpaste, dilute a little with clear spirit or rejuvenator spirit. Water may be used but will not dry as quickly, or give quite such a good finish.