Place the cheese in a mixing bowl and combine gently by mixing using a wooden spoon.
Fill a 22 cm spring-form cake tin with the mixed blue cheese and press down to compact into a cake shape. Place in the freezer to set for 1 hour.
While the cake is setting, place the white chocolate and sour cream in a bowl set over a pot of just-simmering water. Melt the white chocolate into the sour cream until perfectly smooth.
Remove the set Gorgonzola cake from the cake tin and place on a cake stand. Spread the frosting over the top of the cake and serve.