I need to make a grey candy melt shell for a giant cupcake. I was going to combine white and a few black melts, but now the only store I can get them from is sold out of black, and I don't know if they'll have them in time for when I need them. What type of coloring can I use to make grey? Would any kind of powdered coloring work? I'v heard the gel colors can't be used, but are all powders ok?
if you use gel colors when the candy is in its liquid form, it will usually cause the candy to seize. if you want to add color in melted form, it needs to be oil-based candy color. i think i have read powder will work too, but i have no personal experience (i also think i read somewhere that it can be grainy).
most craft stores will carry a small oil candy color "kit" of four colors, one of them being black.
if you are making candy clay, then you CAN add the regular color gel after it has aged and been kneaded.
Wilton has there own oil based colors for the candy melts.