4 eggs, separated
175 g/6 oz/1 cup icing (confectioners') sugar, sifted
Grated rind of 1/2 lemon
60g/2.5 oz plain (all-purpose) flour
60g/2.5 oz potato flour
2.5 ml/0.5 tsp baking powder For the filling:
45 ml/3 tbsp caster (superfine) sugar
15 ml/1 tbsp cornflour (cornstarch)
300 ml milk
3 egg yolks, beaten
50 g/2 oz chopped mixed nuts
150 ml double (heavy) cream For the topping.
100g/4 oz/1 cup plain (semi-sweet) chocolate
30 ml/2 tbsp double (heavy) cream
25 g/1 oz white chocolate, grated or
sliced into curls
Beat the egg yolks into the icing sugar
and lemon rind. Stir in the flours and baking powder. Whisk the egg
whites until stiff, then fold into the mixture using a metal spoon.
Spoon into a greased and lined 23 cm/9 in cake tin (pan) and bake in a
preheated oven at 190°C/375°F/gas mark 5 for 20 minutes until golden
brown and springy to the touch. Leave to cool in the tin for 5
minutes, then turn out on to a wire rack to finish cooling. Slice the
cake horizontally into three layers.
To make the filling, blend the sugar and cornflour to a paste with a
little of the milk. Bring the remaining milk just to the boil, then
pour on to the cornflour mixture and blend well. Return to the
rinsed-out pan and stir continuously over a very gentle heat until the
custard thickens. Beat in the egg yolks over a very low heat without
allowing the custard to boil. Leave to cool slightly, then stir in the
nuts. Whip the cream until stiff, then fold into the custard. Sandwich
the layers together with the custard.
To make the topping, melt the chocolate with the cream in a heatproof
bowl set over a pan of gently simmering water. Spread over the top of
the cake and decorate with grated white chocolate.