I heard a problem is that the white and the dark chocolate gets separated, how do you make this seamless? Does it have to do with using chips or chopped chocolate?
What I mean is……….the chocolates for some reason are not sticking together after serving in my friend’s trial runs. When they are chopped they fall apart.

Melt both chocolates and swirl together with a knife. An alternative is to make the base from the dark chocolate and then top with the white chocolate and crushed candies.