Heat oven to 325°F.

In the microwave or using a double boiler on the stovetop, gently melt the white chocolate. Take care to not let it scorch. Set aside to cool to room temperature.

Line a 13 x 9 inch pan with foil, with ends of foil extending over the two long pan sides. In a food processor, pulse Oreos (whole, do not remove the filling) until finely ground. Drizzle in melted butter and blitz a few more times to evenly combine. Press onto bottom of prepared pan.

In a large bowl, beat cream cheese and sugar with electric mixer until blended. Add sour cream and mix well. Add eggs, 1 at a time, beating on low speed after each, just until blended. Add cooled white chocolate and vanilla, and beat again to combine.

Pour filling mixture over crust and tap the pan gently on the counter a few times to settle the filling in. Bake for about 55 minutes, or until center is just set. Remove from oven and let cool completely at room temperature, then refrigerate for at least 4 hours or overnight. Cut around the edge of the pan and then use foil handles to lift cheesecake from pan before cutting into bars. To achieve clean cuts, dip the blade of a long non-serrated knife into a tall glass of very warm water, wipe it clean, and then make your cut. Wipe blade clean on a paper towel and repeat.

Serve cheesecake bars chilled, with a sprinkle of chocolate cookie crumbs over the top, plus fresh raspberries.