Preheat the oven to 200 degrees Celsius. Lightly grease six medium sized ramekins with butter and dust with cocoa powder.
Place the chocolate and butter into a bowl. Place the bowl over a saucepan, on a medium / low fire, with about 1 inch of boiling water inside, so that the water doesn’t touch the bowl. Stir until the chocolate is completely dissolved and smooth. Add a pinch of grided salt.
Using an electric mixer, beat the eggs, egg yolks and sugar in a large bowl until pale and doubled in volume; this will take about 3 to 5 minutes.
Fold in the melted chocolate mixture very gently so you don’t cook the eggs. Add the flour and whisk until smooth.
Pour into the prepared moulds, dividing equally. At this point you can either refrigerate your mixture for later use or you can bake it straight away.
Bake for 8 to 10 minutes (or 12 if it has been refrigerated), or until slightly puffed and just set around the sides. Let the fondants rest for 3 to 4 minutes.
In the meanwhile make your mascarpone cream by simply mixing the mascarpone and the icing sugar together.
To serve, run the tip of your knife around the mold to release your puddings, tip the moulds onto a plate and lightly tap the bottom to release fondants. Dust with icing sugar and serve with the mascarpone cream.