Step 1: Preheat your oven to 350°F (175°C) and grease a 9×5 inch loaf pan with butter or non-stick spray.
Step 2: In a medium bowl, whisk together the flour, baking powder, and salt until well combined.
Step 3: In a large bowl, cream the softened butter and granulated sugar together using an electric mixer until light and fluffy (about 3-5 minutes).
Step 4: Beat in the eggs one at a time, then stir in the vanilla extract.
Step 5: Gradually add the dry ingredients to the wet ingredients, alternating with the sour cream. Mix until just combined.
Step 6: Gently fold in the white chocolate chips and raspberries by hand using a spatula.
Step 7: Pour the batter into the prepared loaf pan and bake for 55 to 65 minutes, or until a toothpick comes out clean.
Step 8: Allow the cake to cool in the pan for 10 minutes before transferring to a wire rack to cool completely.