01 - Preheat oven to 325°F. Line a 9x9-inch baking pan with parchment paper, leaving an overhang to facilitate removal.
02 - Combine graham cracker crumbs, sugar, and melted butter in a bowl until blended. Firmly press mixture into the bottom of the prepared pan. Bake for 10 minutes, then allow to cool slightly.
03 - In a small saucepan, combine raspberries, sugar, and lemon juice. Cook over medium heat, stirring and mashing, until the raspberries break down and the mixture thickens, approximately 5 minutes. Strain through a fine mesh sieve to remove seeds. Set aside to cool.
04 - In a large bowl, beat cream cheese and sugar until smooth and creamy. Add eggs one at a time, mixing well after each addition. Stir in vanilla extract and sour cream. Gently fold in the melted white chocolate until just incorporated.
05 - Pour the cheesecake filling evenly over the cooled crust. Drop spoonfuls of the raspberry puree on top and use a toothpick or skewer to create a gentle swirl effect.
06 - Bake for 30 to 35 minutes, until the center is nearly set and edges are slightly puffed. Avoid overbaking to maintain a creamy texture.
07 - Allow bars to cool to room temperature, then refrigerate for at least 3 hours before cutting into 16 bars.