If making raspberry jam, it's crucial to use sterilised jars to store it. To clean the jars, preheat the oven to 140C/120C Fan/Gas 1. Wash the jars well in warm soapy water then rinse thoroughly ...

with a raspberry jam layer and a marbled chocolate topping. Preheat the oven to 170C/160C Fan/Gas 3½. Lightly grease a 20cm/8in square cake tin and line with baking paper; leave some paper ...