First put the unopened condensed milk packs (tetrapaks) in a saucepan with water and simmer for at least 2 hours at medium temperature, then let them cool down a little.
Crumble the shortbread biscuits and place in a baking dish. Spread the contents of the condensed milk packets on it and whip the cream until stiff and spread on it as well. Finally, the chocolate sprinkles on the top. Then it is best to put it in the refrigerator overnight.