Chill the heavy whipping cream, then beat it with a mixer until stiff peaks form. In a separate bowl, gently stir the sour cream, then fold it into the whipped cream.

Dissolve the gelatin in a little hot water. Let it cool slightly, then gradually add it to the cream mixture, stirring well. Pour the mixture into a bottomless mold, filling it to the top, and shape it to create a hill-like slope.

Mix some shredded coconut with green food coloring to make grass, and leave some plain for snow. Once the cake has set in the refrigerator, carefully remove the mold. Arrange ladyfingers around the cake to form a fence and tie them with a ribbon. Decorate the top with your choice of decorations. Chill in the refrigerator until ready to serve.

This cake is charming, unique, and delicious, with no added sugar or butter.