Place a shallow layer (½ to ¾ inch) of fruit and liquid into a casserole dish and put into a 350° oven to pre-heat the fruit while preparing the batter for the 'cake' topping
Beat the egg and sugar, add the melted butter and beat again. Add the flour and milk and combine at a slow mixer speed. Remove the heated casserole and fruit from the oven, pour the cake mixture over the fruit base (don't worry if it is a bit uneven and doesn't completely cover the fruit/liquid). Return casserole to the oven and cook for 30 minutes, or until cake topping is brown and cooked through (test with skewer). Serve warm, sprinkling with sifted icing sugar just before serving.