Preheat the oven to 200°C.
Place the dark chocolate and the butter in a bowl and melt over a pan of simmering water.
Beat together the eggs and the sugar until thick. Stir in the melted chocolate and then sift in the flour.
Line stainless steel serving rings with baking parchment. Pour a little of the dark chocolate mixture into each mould and then add two squares of white chocolate. Top with the dark chocolate mixture so that the moulds are 3 quarters full.
Transfer to the oven and bake for 6 minutes.
Jeat a frying pan and then add the sugar. Melt, without stirring, to form a caramel. Over a low heat, mix in the butter. Once the butter has melted, stir in the cream.
Remove the serving rings from the moelleux and serve with the caramel sauce.
This dessert can be served hot or cold.
«Vary the cooking time from 4 to 8 minutes - the longer the moelleux are in the oven, the less liquid they will be in the centre.»