Preheat oven to 350°F (180°C) Gas 4. Grease and base-line a 9 inch springform tin.

Crumble the cake into a bowl. Separate two of the eggs, putting the yolks and remaining whole egg into a bowl with the sugar. Put the milk and butter into a saucepan and bring almost to the boil.

Beat the yolks and sugar together and pour the milk on to them, stirring constantly. Strain over the cake crumbs. Add the lemon rind and cinnamon, mix well and leave to stand for 15 minutes.

Meanwhile, wash and halve the plums, discarding the stones. Dry thoroughly on kitchen paper.

Whisk the 2 egg whites in a large bowl till stiff but not dry and fold into the crumb mixture with a metal spoon. Pour the mixture into the tin.

Arrange the plums cut sides down on the mixture and bake in the centre of the oven for about 50 minutes till set.

Remove from the oven and leave to cool in the tin, then chill for 3 — 4 hours. Remove pudding from tin and place on a serving dish. Serve cut into slices, with pouring cream.