A refreshing summer dessert that starts with either a homemade or store-bought cake, which is then filled with a delicious orange custard sauce.
In the top of a double boiler, mix the eggs, sugar, and juice and zest of the orange and lemon. Cook over boiling water for about 10 minutes, or until the custard sauce is thickened, stirring occasionally. Cool thoroughly.
Whip the cream. Fold the cooled custard sauce into the cream. Cut the sponge cake into four layers. Fill and frost with the custard filling. Chill for several hours or overnight.