Remove ice cream from freezer 30 minutes before using. Place chocolate sandwich cookies in food processor. Whirl until crumbed. Add butter. Whirl until combined.
Stand wafer cookies around inside edge of 9-inch springform pan. Reserve 3/4 cup of chocolate crumb mixture. Spoon remaining crumb mixture into pan; press evenly over bottom.
Stir peanut butter, honey and oil in small dish until blended. Place softened ice cream in large bowl. Drizzle about half of peanut butter mixture onto ice cream; fold together to swirl.
Spoon half of the ice-cream mixture into the prepared pan; spread level. Sprinkle evenly with remaining chocolate crumb mixture, pressing mixture down with back of spoon.
Spoon on remaining ice cream; spread level. Place the cake on a baking sheet and place in freezer. Freeze until cake is solid, at least 6 hours or overnight.
To serve, stir fudge sauce in glass measure to loosen, but do not warm. Spoon remaining peanut butter in blobs over top of cake along with blobs of fudge topping. Swirl together with the tip of a knife. Let stand for 10 minutes.
Slice cake into wedges. Makes 16 servings.