Mix the butter at room temperature with the condensed milk. Beat with a mixer until the cream thickens and is covered with light ripples. At the end of beating, you can add vanilla if you wish.
Before spreading the first layer, soak it with juice from the compote. This will make the cake moister.
Spread the cream on the first cake layer.
Place the second sponge cake on top of the first one, which has been soaked and generously coated with cream, then soak it with juice and coat it generously with cream. Remove the pits from the cherries and cover the sponge cake completely with the berries.
Cover with the last layer, soak with sweet juice, and spread cream on the top and sides.
Grate the chocolate using a coarse grater.
Sprinkle the crumbs over the top and sides of the cake.
Let the cake sit in the refrigerator for at least 3-4 hours so that the cherry juice and cream properly soak into the layers.