Combine gelatin, sugar, salt and chocolate chips in double boiler. Beat egg yolks slightly with milk; stir into gelatin mixture. Cook over boiling water, stirring constantly until chocolate is melted and mixture is slightly thickened.
Remove from heat, stir in rice. Chill until mixture is quite cold and has begun to set.
Beat 1/2 cup heavy cream until stiff. Beat egg whites until foamy; add 2 tablespoons sugar and continue to beat until stiff peaks form.
Break up mint jelly with a fork; fold into chocolate mixture along with whipped cream and egg whites. Chill until mixture begins to set.
Spoon into 6 sherbet glasses. Whip 1/2 cup heavy cream; beat in 1 tablespoon mint jelly. Spoon over pudding in sherbet glasses. Top with additional mint jelly, if desired. Makes 6 servings.