01 - Preheat the oven to 350°F. Line a 9-inch square baking pan with parchment paper, leaving an overhang on the sides to facilitate removal.
02 - Combine graham cracker crumbs, melted butter, sugar, and salt in a bowl. Press the mixture evenly into the bottom of the prepared pan. Bake for 8 minutes and allow to cool slightly.
03 - In a small saucepan, combine raspberries, sugar, and lemon juice. Cook over medium heat, stirring and mashing berries until thickened, about 5 minutes. Strain through a fine mesh sieve to remove seeds. Set aside to cool.
04 - Beat cream cheese and sugar together until smooth and creamy. Add eggs one at a time, mixing well after each addition. Incorporate vanilla extract and sour cream, then gently fold in melted white chocolate until combined.
05 - Pour cheesecake filling over cooled crust, spreading evenly. Drop spoonfuls of raspberry puree over the filling and use a knife or skewer to swirl the puree for a marbled effect.
06 - Bake for 25 to 27 minutes, until the center is just set but still slightly jiggly. Avoid overbaking.
07 - Allow to cool to room temperature, then refrigerate for at least 2 hours before cutting into bars.