To make an iphone cake, any great tips on how to get fine line detail (white on black)? If I just use white royal, the black will bleed through the white. Is there something I could add to the icing to keep it white? Or is there a way to paint it on with food color (but again, without the black coming through)?

Any ideas would be appreciated! Thanks for your help!

let the cake crust before you pipe, then use royal icing. YOu should be fine.