100g dark chocolate 100g butter 50g plain flour 150g caster sugar 3 eggs
Brush a 22cm springform pan with melted butter and line with paper.
Melt the chocolate with the butter in a basin over simmering water. Beat the flour, eggs and sugar together until thick and pale. When the chocolate and butter are melted together, pour them onto the egg mixture and combine thoroughly. Pour into the prepared tin, and bake in a moderate oven for 35-40 minutes.
The tart rises during baking, then settles back on cooling. It will appear to be uncooked in the centre, but don't cook any further or it will turn into chocolate cake! Transfer to a plate when cool.
It will keep 2 or three days, but should not be refrigerated.