If you cannot find kataife/kunafa/knafeh pastry, you can cook some filo pastry, then crush it finely and use this instead. It is the closest alternative to the specialist Greek pastry.
Toast the pastry until it is a beautiful golden colour. Make sure the pan used is large enough, or alternatively cook it in two smaller batches. Making sure the pastry is dry and crispy will give you the perfect texture for the Dubai chocolate bar filling.
I would definitely recommend using a pistachio cream rather than a pistachio butter. A pistachio butter will contain more natural oils than a cream, giving the finished dessert more of an oily texture. I link to the one I used in the recommended table below.
To split the chocolate egg neatly, warm a large sharp knife in hot water (I fill a container with water and let the knife rest in it for a few minutes). Dry it off thoroughly, then gently push the sharp edge around the seam of the egg, where the two halves join. Work your way around the egg gradually (be patient!), warming the knife again and drying off as needed, until the egg halves separate.
When pressing the pistachio knafeh into the chocolate shell, be careful not to press too hard in case you crack the shell. I may have done this myself in the past!
This no bake cheesecake can be enjoyed as soon as it is assembled, however I find it is better being chilled to set before digging in for perfect results.