Put the fruit in a pan with a drop of two of water, and cook slowly until softened. Put through a nylon sieve. Measure the puree and take the ingredients from above. Put the puree into a double saucepan or a bowl over simmering water. Add the butter and sugar and dissolve.
Beat the eggs lightly, strain into the mixture and stir until it thickens. Do not allow to get too hot or boil as it could curdle.
When thick, pot and store. Eat within 3 months and keep in the fridge.
For the cake
Preheat the oven to 190c/gas mark 5. Grease 18cm sandwich tins and line the base of each with a round of greased greaseproof paper.
Cream the butter and sugar together until pale and fluffy. Add the egg a bit at a time. Beat well after each addition. If it starts to curdle, sprinkle in a little of the flour and this should bring it back together.
Now fold in half the flour, using a metal spoon and then fold in the rest gently.
Divide the mixture between the cake tins and level off. Bake both cakes on the same shelf if you can for 20 minutes or until firm to the touch and golden brown. They will also be ready when they have shrunk away from the edge of the tin. Try not to open the oven until at least 15 minutes of cooking time has elapsed otherwise it will sink.
Turn out onto wire racks – cool. When the cakes have cooled, spread with the curd, then the cream. Sandwich together and then dust with lots of icing sugar.