01 - Preheat the oven to 325°F. Line an 8x8-inch baking pan with parchment paper, leaving an overhang for easy removal.
02 - In a medium bowl, combine graham cracker crumbs, sugar, and melted butter. Press firmly into the bottom of the prepared pan. Bake for 8 minutes, then let cool slightly.
03 - In a small bowl, mash raspberries with sugar and lemon juice until slightly syrupy. Set aside.
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. Mix in vanilla, then blend in melted white chocolate and sour cream until fully incorporated.
05 - Pour cheesecake filling over the cooled crust and smooth the top. Drop spoonfuls of the raspberry mixture over the cheesecake batter. Use a skewer or knife to gently swirl the raspberry sauce into the filling.
06 - Bake for 30 to 35 minutes, or until the center is just set and the edges are lightly golden. Allow bars to cool to room temperature, then refrigerate for at least 2 hours before slicing.
07 - Lift the bars out using the parchment overhang. Cut into 16 squares and serve chilled.