You can freeze an un-iced carrot cake for up to 3 months, well-wrapped in clingfilm. Carrot cake is very forgiving. As an oil-based cake it's very easy to throw together without much advance warning.
Preheat the oven to 180C/170C Fan/Gas 4. Butter the sides of a deep 20cm/8in cake tin. Drain the pineapple slices and leave to dry on kitchen paper. Put the soft brown sugar and 60g/2oz of the ...