For the cream, mash the butter and add condensed milk to it. Mix well until smooth or use a mixer.
Slice the grapes and strawberries thinly, removing the stems.
Assemble the cake in layers. Spread the first layer with cream and put the berry filling on top. Do not skimp on the cream to ensure the cake is well soaked.
Repeat this procedure with each cake layer, spreading cream and adding berries. Decorate the last top layer with more berries, add some grated chocolate or powdered sugar on top.
Put the finished cake in the refrigerator, let it sit and soak for 10-20 minutes. Cut the cake and arrange on serving plates. Decorate with fresh mint leaves or ground cinnamon.