Let the berries thaw for about 15 minutes. Cream butter, 40 g sugar and salt. Stir in eggs one after the other. Mix flour and baking powder, alternately stir in with buttermilk. Heat up the waffle iron and grease it lightly.
Puree the icing sugar and rum with the fruits to a creamy mixture. Freeze the mixture.
Bake 8 waffles one after the other from the dough, keep warm. Mix sour cream, vanilla and 20 g sugar. Cut out 6 balls from the ice cream mixture. Arrange the waffles with the Blitz ice cream. Add vanilla sour cream.