How to make
Separate 3 1/5 cups (750 ml) of the milk and boil it. To it add the sugar and stir so you get a homogenous mixture.
Beat the eggs and add the flour, vanilla and rum to them. Mix the resulting mixture with the sweetened milk. You need to get a creamy liquid.
Crumble the biscuits and distribute them along the bottom of a tray. Cover this layer with some of the remaining milk and the cream you just prepared.
Arrange another layer of biscuits and repeat this procedure. Once you're out of biscuits, finish off the dessert with a layer of cream. Sprinkle with ground walnuts and chocolate on top. Leave the cake in the fridge for 8 hours.
