Combine pudding mix and sugar in a large bowl. Gradually add skim milk and evaporated milk, stirring with a wire whisk until smooth. Stir in marshmallows, chocolate morsels, and peanuts.
Pour chocolate mixture into freezer can of a 2-quart hand-turned or electric freezer. Freeze according to manufacturer's instructions. Pack freezer with additional ice and rock salt, and let stand at least 1 hour before serving.