Melt butter in a large pan over medium heat. Add in the kataifi and cook, toasting the kataifi until deep golden brown and crunchy. Remove from heat and set aside to cool down.
In a double broiler, add in all the chopped chocolate. Stir when the chocolate starts to melt- the chocolate should be smooth.
In a chocolate bar mold, pour a thin layer of the melted chocolate (swirl some melted white chocolate for decor) and spread a thin layer of the semi sweet and milk chocolate chips into each slot. Make sure there's plenty of room left still in each mold slot. Put into the fridge to allow the chocolate to set for 10 minutes.
In a large bowl, add the toasted kataifi, pistachio cream, maple syrup and tahini. Mix well to evenly incorporate.
Remove the chocolate mold from the fridge. Pour a thick layer of the kataifi mixture into each mold, filling them up. Use a spoon to flatten the kataifi mixture down. Pour the remaining melted chocolate on top of the kataifi mixture, then spread the chocolate to evenly coat. Place the molds back into the fridge for 30 minutes-1 hour.
Remove the chocolate bars from the molds. Split in half and Devour!
