Preheat oven to 160°C. Invert the base of a 22cm or 23cm springform tin. Grease, then line base and sides of tin with baking paper. Put cookies in the bowl of a food processor. Process until fine crumbs form.
Add butter and pulse until combined. Press cookie mixture into the base of prepared tin. Refrigerate for 20 minutes. Put cookie base on an oven tray and bake for 15 minutes. Let cool.
Put ½ of the cream cheese in the clean bowl of a food processor and process until smooth. Gradually add remaining cream cheese through food chute, while processing, until smooth.
Add caster sugar, flour, zest, juice, vanilla extract and eggs, then process until smooth. Add sour cream and pulse until smooth. Pour onto cookie base. Bake for 1 hour and 10 minutes or until lightly coloured around the edges and set in the middle, turning oven tray once. Allow to cool completely. Refrigerate cheesecake for 4 hours or overnight.
Sprinkle top of cheesecake evenly with extra caster sugar. Using a cook’s blowtorch, scorch sugar until it melts and forms a crunchy brûlée toffee on top. Serve sprinkled with raspberries.