An Australian cup is 250ml. A plain ring tin is not as deep as a fluted ring so may not be suitable for the amount of mixture. Because of the detailed shape of the cake tin it may not be able to be lined with baking paper, so brush the tin with a thick layer of melted butter and dust with flour or desiccated coconut to prevent sticking. Only use a light flavoured oil such as a ‘lite’ olive, safflower or canola, not strong flavours such as virgin olive oil or peanut oil. The unglazed cake can be frozen for up 3 weeks, allow to thaw in the fridge.