Release the base from a 23cm (base measurement) springform pan and invert. Secure the base back into the pan. Line base and side with baking paper.
Place biscuits in a food processor and process until finely crushed. Add butter and process until combined. Transfer to prepared pan. Use the back of a spoon or a straight-sided glass, spread and press the biscuit mixture firmly over base. Refrigerate for 30 minutes.
Meanwhile, preheat oven to 170°C/150°C fan-forced. Using an electric mixer, beat cream cheese, vanilla and sugar until smooth. Beat in sour cream and flour. Add eggs, one at a time, beating until combined and scraping down the side of the bowl with a spatula.
Pour cream cheese mixture into prepared pan. Bake in oven for 1 hour or until almost set in the centre. Turn oven off. Leave cheesecake in oven, with the door slightly ajar, until cooled (this will prevent the cake from cracking). Refrigerate overnight.
Place caster sugar and 2 tablespoons water in a frying pan. Bring to the boil. Boil, swirling pan occasionally, for 2-3 minutes or until syrup thicken and reduces. Add strawberries and gently stir to coat in syrup. Cook for 1-2 minutes or until syrup turns pale pink and strawberries are slightly warmed through (do not overcook). Remove from heat. Stir in raspberries. Set aside to cool
Remove cheesecake from pan. Decorate top of cheesecake with berry compote and flowers, if you like
Tips & Hints:
To cut cheesecakes, dip your knife into a bowl of hot water. Wipe dry. Use the hot knife to cut, reheating and drying the knife between slices.