Preheat the oven to 190C/Gas5; line 3 baking trays with baking paper
Whisk the egg yolks with half of the sugar and the vanilla until very pale
Beat the egg whites with the salt and the rest of sugar, until soft peaks form
Fold the egg whites into the egg yolk mixture; fold the flour into the egg mixture
Place half the mixture in a piping bag fitted with a 1cm nozzle and pipe fingers well apart; repeat with the other half of the mixture
Bake for 15 minutes until golden and firm to the touch; remove from the oven and cool
Mix the juice of the lemon with the limoncello and 2 tbsp water
Mix the lemon curd with the cream cheese; add the double cream and beat until smooth and creamy; stir in the finely diced stem ginger and lemon zest
Line a 900g loaf tin with clingfilm; dip 8 sponge fingers in the lemon juice mixture and line the base of the tin; smooth on half the creamy filling, top with 8 more dipped sponge fingers, then the remaining filling; finish with 8 dipped sponge fingers
Cover with clingfilm, weigh down with some cans and chill overnight; turn out the pudding and slice; dust with icing sugar and sprinkle with extra lemon zest and stem ginger
8 servings