01 - Preheat oven to 350°F. Line a 9-inch square baking pan with parchment paper, leaving overhang on the sides.
02 - In a bowl, combine graham cracker crumbs, melted butter, sugar, and salt. Mix until the texture resembles wet sand. Press evenly into the bottom of the prepared pan. Bake for 10 minutes. Set aside to cool slightly.
03 - In a small saucepan, combine raspberries, sugar, and lemon juice. Cook over medium heat for 4–5 minutes, stirring and mashing the berries until thickened. Strain through a fine sieve to remove seeds, if desired. Let cool.
04 - In a large bowl, beat cream cheese and sugar until smooth and creamy. Add eggs, one at a time, beating well after each addition. Mix in vanilla extract and sour cream. Add melted white chocolate and flour; blend just until combined.
05 - Pour cheesecake filling over the cooled crust and smooth the top. Dollop raspberry sauce over the filling in small spoonfuls. Use a skewer or knife to gently swirl the raspberry sauce into the cheesecake.
06 - Bake for 30 minutes, or until edges are set and center is slightly wobbly. Cool to room temperature, then chill in the refrigerator for at least 2 hours before slicing into bars.