Make the chocolate cake by combining the sugar, egg, and vanilla in a medium bowl and mixing with an electric mixer on high for 2 minute. Add the oil and shortening and mix well, then add the water and mix until smooth.
In another medium bowl, combine the flour, cocoa powder, baking powder, baking soda, and salt. Pour this dry blend into the bowl with the wet ingredients and mix until smooth. Pour into a well-greased 10-inch springform pan and bake in the preheated oven for 25 minutes.
While the cake is in the oven, prepare chocolate icing. Once the cake is completely cool, spread icing over the top of the cake, reserving some for garnishing the cake later. Freeze cake with icing for 1 hour.
Prepare the oreo cheesecake layer by mixing the heavy cream, sugar, and vanilla in a medium bowl with an electric mixer on high until the cream forms stiff peaks. Mix in the softened cream cheese until smooth. Spread 1/3 of the mixture over the icing on the cake. Place whole oreo cookies in a single layer across the entire cake. Follow with the remaining cheesecake mixture. Chill for 1 hour.
Make the oreo mousse layer by mixing 1/2 packet of the powdered gelatin with the hot water. Refrigerate until set. Once set, place in cold water to soften gelatin enough to loosen it from the pan. Place softened gelatin into a double boiler and melt.
In a separate double boiler, melt the chocolate, being careful not to burn it. Add melted chocolate to gelatin and mix well.
Whip egg yolks by hand in a small bowl to soft foamy peaks. Mean while, bring honey to a boil. Pour hot honey onto the yolks stirring constantly. Fold the melted chocolate into the yolk mixture. Heat the milk in a small saucepan. Stir the milk into the chocolate mixture.
In a large bowl, whip the cream to soft peaks and fold into the chocolate mixture. Add the crushed oreos to the mixture and mix well.
Pour enough mousse over the cheesecake layer to form a layer about 1/2 inch thick. There may be mousse left over. Chill for at least 2 hours or overnight.
Prepare chocolate ganache layer by whisking together the egg, cream, and sugar in a medium metal bow. Set the bowl over water that is simmering in a medium saucepan over medium/low heat (you can also use a double boiler pan for this) and whisk for 6 minutes, or until thick. Remove the bowl from the heat, add the chocolate chips (not the mini chocolate chips), and mix with a spoon until smooth. Spread over the oreo mousse layer. Chill at least 1 hour.
Load the reserved chocolate icing into a piping bag. Remove cake from springform pan and pipe icing into 12 even circles around the side of the cake. Lay 1/2 oreo cookie with cream filling removed back onto each mound of icing.
Press mini chocolate chips around the sides of the cake. Press firmly so that the chips stick. Chill the cake for at least another hour, then use a serrated knife to cut the cake into 12 slices.
Serve with a mound of whipped cream and oreo cookie pieces to the side.