Crush cookies in a food processor and mix with melted butter; press firmly into the bottom of a 9-inch springform pan.
Freeze the crust for 15 minutes to set.
Spread the softened chocolate ice cream evenly over the crust and freeze for 30 minutes.
Spread chilled fudge sauce over the chocolate ice cream layer and top with the chocolate cookie crumbs; freeze for 30 minutes.
Spread the softened vanilla ice cream over the fudge layer and smooth the top with an offset spatula.
Cover and freeze for at least 4 hours or until completely firm.
In a chilled bowl, whisk heavy cream, powdered sugar, and vanilla extract until stiff peaks form.
Remove the cake from the springform pan and frost the top and sides with the prepared whipped cream.
Decorate with sprinkles and return to the freezer for at least 1 hour before serving.