Melt the chocolate in a bowl over a small pot of boiling water (make sure water does not touch the bowl), or microwave. Stir until smooth, let cool a couple of minutes. Pour ½ of the chocolate on the bottom of the pan. Place in the fridge to set.
In a medium bowl whip the cream until stiff. Set aside.
Separate the Oreo cookies, the white center place in a heat resistant bowl. Then crush the cookie part of the Oreo cookies into crumbs mix with the melted butter to form coarse crumbs.
Place the bowl with the white centres of the Oreo cookies over the pot of boiling water and heat just until softened, let cool. Then fold into the whipped cream and set aside.
Remove base from the fridge, layer with half the crushed cookies, then the creamed mixture and then the remaining crushed cookies. Gently press down to flatten. Top with other remaining melted chocolate (if it is hard, just place over boiling water again, let cool slightly). Place in the fridge for a 2-3 hours or even over night to harden. Decorate with shaved or shredded chocolate then cut and serve. Enjoy!