Cream all the ingredients. You can use the butter cream to top cupcakes, sponge cake or spread swiss rolls.
Just spread the butter cream and top with another wafer until you use up all of the filling and wafers. Let sit at room temperature for at least 3 hours before cutting.
Andruty (pronounced : androotyh) are thin, plain, crispy and fragile wafers which you can buy in grocery stores around Poland.