I know that you can use pearl dust on fondant and royal icing to make it shimmer, but what about crusted buttercream? I've never used pearl dust or anything like it, so I'm not sure what the best way is to dust it on. Do I use a paintbrush and brush it on? Would it be better to draw the design on with royal icing instead of buttercream and then use the dust? Thanks in advance for any help!
I've used the Wilton dusts over crusted buttercream. It gets a little glittery but not the Wow! effect that you get painting fondant (or probably painting RI).
I have had good luck putting the buttercream-iced cake in the freezer, taking out when hardened, then dusting with pearl dust. It just glistens! Same with pearl-dusted buttercream roses-make the roses on waxed paper, put in freezer; when hardened, remove rose-one at a time, dust, then remove another. If I want metalic gold roses in buttercrream, I color buttercream with gold food color, make roses and put in freezer, then dust with old gold or super gold (removing roses from freezer, one at a time so they don't thaw before they are dusted). For silver roses, I use black food color to get a grey color, freeze, then dust with moonstone silver. This gets beautiful gold, silver, and pearl roses!