Melt chocolate and butter in a double boiler. Set aside to cool slightly.
Beat in another bowl the egg whites and 1 tablespoon of sugar until soft peaks form.
In a third bowl, beat together the egg yolks, 2 tablespoons sugar and a pinch of salt until combined and fluffy, about 4 to 5 minutes.
With a spatula, fold egg yolk mixture into the chocolate and butter mixture.
Then, fold the egg whites into the chocolate mixture.
Divide among ramekins or bowls and allow to chill in the fridge for up to 2 days and for as little as 2 hours.
Serve with whipped cream, if desired