Pre heat the oven to 180C.
Melt the butter and chocolate together in a bowl over some hot water
Add the egg and egg yolk, mixing well.
Fold in the flour an icing sugar, beat until glossy.
Butter 3 or 4 ramekins and chill in the fridge. Repeat with another layer of butter.
Fill the ramekins three quarters full and place into the pre-heated oven for 8 to 10 minutes. They should be slighly wobbly in the middle. Leave for one minute and turn out onto a plate.