There are two reasons your chocolate layers could be separating:u003cbr/u003e1. If the dark chocolate layer is left to chill too long between pouring the white chocolate on top.u003cbr/u003e2. If the kinds of chocolate you are using contain incompatible fats - eg the dark chocolate contains cocoa butter, but the white chocolate contains palm kernel oil. To avoid this, opt for white chocolate that contains cocoa butter!