Line an 8-inch springform pan with plastic wrap, leaving overhang.
Place the chocolate cake layer in the bottom of the pan.
Mix crushed cookies with melted butter and press over the cake layer. Freeze 15 minutes.
Spread softened vanilla ice cream over the crumble layer. Freeze 1 hour.
Spread softened chocolate ice cream over the vanilla layer. Freeze at least 4 hours or overnight.
Whip cold heavy cream with powdered sugar and vanilla extract to stiff peaks.
Remove the cake from the pan and frost with whipped cream.
Add toppings and freeze at least 1 more hour before slicing.