For the Tiramisu, whip Rama Cremefine with 3 packets of vanilla sugar until stiff. Put the curd cheese in a bowl and mix with powdered sugar, freshly grated lemon zest and some lemon juice.
Fold in the whipped Cremefine. Pour cold coffee into a shallow container, add rum and stir. Briefly dip the biscuits into the coffee mixture and place them in a row in the baking dish.
Spread a layer of cream on top and repeat this process twice more until the biscuits and cream are used up.
At the end, smooth the cream and chill. Before serving, sprinkle thickly with cocoa.