Begin by preheating your oven to 160 degrees Celsius and preparing a 20 cm round cake tin with baking paper.

Crush the digestive biscuits into a fine powder and combine with the melted butter. Press this mixture firmly into the bottom of the cake tin.

In a separate bowl, blend the cream cheese, sugar, and flour until smooth and well combined.

Gradually add the eggs, one at a time, ensuring each egg is fully incorporated before adding the next.

Mix in the sour cream and vanilla extract until the mixture is smooth and creamy.

Pour the cream cheese mixture over the biscuit base in the cake tin.

Use a blender to puree the raspberries and raspberry jam. Drizzle this mixture over the cream cheese layer, then use a knife to gently swirl it into the cream cheese to achieve a marbled effect.

Bake the cheesecake for approximately 1 hour or until it is set with a slightly jiggly centre. Allow the cheesecake to cool in the oven with the door open, and then refrigerate it for at least 4 hours or overnight before serving.