TO MAKE CAKE: 1 - Grease a 9 x 13" pan. Combine wafers and 1/3 cup melted butter and press into bottom of pan. Place in freezer for 15 minutes. 2 - Spread half of the ice cream over crust. Sprinkle with crushed skor bars and press into ice cream layer. Carefully spread remaining ice cream over crumbs. Sprinkle with peanuts and freeze for 2 - 3 hours. TO MAKE TOFFEE SAUCE: 1 - In a small saucepan, melt 1/2 cup butter over low heat. Stir in brown sugar and cream. Cook and stir constantly over low heat until sugar has dissolved. Remove from head and add vanilla. TO SERVE: Remove cake from pan and cut into slices. Pour warm or cold toffee sauce over each serving.