cake paint?

[yeahbaby]

Any idea where to buy or which brand is the one to use?

I use a little food colouring gel and mix it with paintmate or vodka and paint it on. Never used a commercial version.

Food colouring gels are available in baking shops/online or Morrisons sell a limited range.

i have the lakeland gel colours set, could i use that to paint on?

Yup, as long as you mix them with some alcohol which helps them dry out when you paint them on - if you use colours neat they run and are sticky.