Put half of the sugar with the cream in a pot on the stove to caramelize. As soon as you obtain a light and smooth caramel, start pouring in 3 cups (700 ml) of warm milk and stir until the caramel is completely dissolved in the milk. Mix with the remaining sugar.
Separately beat the eggs with the flour, vanilla and remaining milk. Stir constantly and pour this mixture into the heated caramel and milk and stir until the cream thickens. Then let it cool completely. Beat the confectionery cream until thickened and add a tablespoon of cream at a time, while still beating, to merge the two mixtures.
Pour a little of the cream on the bottom of a rectangular tray. Dip the biscuits in the milk with vanilla and make a layer, top with cream and repeat until you run out of products.
Top with cream, smooth it out and make decorations as desired. Put the biscuit cake with cream-caramel cream in the fridge overnight before serving.