How can I make this cool chocolate shape? I've fallen in love with this picture. 



I am wondering how I can make the white chocolate layer. 

My guesses are:


option A: use a bottle and "pour" melted white chocolate above it
-- downside: ? the chocolate wouldn't get nice and smooth as in the picture.
option B: use a 2 pieces plastic moulder(like when making Eastern eggs) and "pour" white chocolate above it. Once poured use a different but smaller plastic shell and place it in the moulder in order to flat the chocolate.


Any suggestions?
I think it is more likely that the pastry chef employed a piece of food grade acetate (the link is a sample vendor).

They would have piped the pattern of tempered white chocolate onto the acetate sheet, then rolled it into a cylinder (chocolate on the inside) taping or clamping it shut to set.  Once thoroughly chilled, they would have very, very carefully peeled the sheet from the chocolate.

This is a very advanced technique, especially with white chocolate, which is persnickety and tough to temper, and often not as solid as dark chocolate.  Good luck.