For crust mix together the butter and graham cracker crumbs, Mix well and line bottom and sides of an 8" springform pan. Place in refrigerator to chill, for at least 2 hours. For the filling: In a small pan sprinkle gelatin over 1/4 cup cold water. After 5 minutes add balance of water and heat to dissolve gelatin. Add chocolate to melt it and blend with gelatin. Cream together cream cheese, sugar, peppermint essence and lemon juice. Add chocolate mixture, beating on high mixture. Add chilled evaporated milk, still beating at high speed, keep beating until frothy. Pour into cold crust and refrigerate overnight. Before serving pass thin knife along sides of pan, remove ring and decorate with 1/2 cup whipped cream and chocolate chips.
