Preheat oven to 350ºF (176ºC). Grease and flour pan; set aside. In a medium bowl, Sift together flour, baking powder and salt; set aside. In a large bowl, beat butter, sugar and vanilla until creamy, about 2 minutes. Add eggs one at a time, beating well after each addition. Stir in flour mixture, alternating with milk in three additions; mix well. Fold in white chocolate. Spoon half of batter into prepared pan. Spoon raspberry filling over batter. Spoon remaining batter over filling. Bake 55-60 minutes. Remove from oven and cool 10 minutes in pan. Invert onto cooling rack to cool completely. Sprinkle with powdered sugar and fill center with fresh raspberries just before serving.