Beat the egg yolks until thick and lemon colored. Add the water and slowly add the sugar, beating 2 minutes with a hand beater.
Mix and sift the flour, cornstarch, baking powder and salt and add to the first mixture.
Beat the egg whites until stiff and carefully fold them into the mixture. Blend in the vanilla.
Bake in four 9" cake tins, ungreased, in a quick, hot oven (preheated to 450 degrees) for 15 minutes, or until a toothpick comes out clean.
Put a custard filling between the first and second layers, raspberry jam between the second and third layers, custard filling between the third and fourth layers.
Custart Filling: Mix all custard ingredients in order given and beat well. Cook over low heat until thick, stirring occasionally to keep thickening even.
Cream Frosting goes well on this when chilled.