In a medium, lined slow cooker, whisk together the eggs, cream and salt. Add the chocolate chips, cover and set the slow cooker to high heat to melt, about 30 minutes; whisk until smooth.
Cook on low heat for another 30 minutes. Scrape down the slow cooker; whisk the pudding. Cook until set at the edges but loose in the center, 1 hour 15 minutes; whisk until smooth. Hold on the warm setting.
Just before serving, whisk the pudding. Spoon into mugs or bowls and top with the marshmallow cream. Garnish with the grated chocolate.