Serves 4Set a metal bowl over a pan of simmering, not boiling water. Combine the chocolate and milk in the bowl and heat until the chocolate is melted. Whisk in the sugar, vanilla, and salt. Add the eggs one at a time, whisking well after each addition. Regulate the heat so that the water stays at a constant slow simmer. Cook the pudding, stirring often, until thick and an instant read thermometer reaches 160ºF, 5 to 10 minutes. Pour into four 1/2-cup ramekins and cool to room temperature. Cover with plastic wrap and refrigerate until well chilled, at least 3 hours. The pudding can be made up to 2 days in advance. Top with a dollop of whipped cream just before serving.