Boil milk in thick bottom pan. Whip in eggs, sugar, and cake flour. The eggs and sugar are mixed first then add the flour to egg. Make sure you use CAKE flour. Temper egg mix with half cup of milk or it'll be too thick to pour into milk in pan. You MUST whip this vigorously as its being poured into boiling milk or it'll scorch. Once everything has come back to boil pour out onto marble slab or tray, sprinkle liberally with granulated sugar ( to prevent crusting) and let cool, when cool refrigerate until completely cold. Place in mixer and beat with paddle, when most of the lumps are gone add dark rum and vanilla.