Preheat the oven to 180°C (350°F) and line a loaf tin 20x10x6cm (8x4x3inch) with oil and parchment paper.
In a bowl of an electric mixer fitted with a paddle attachment add the butter, oil, and sugar. Beat at medium-high speed until creamed, about 3 to 5 minutes.
Add the eggs to the creamed butter and sugar mixture one at a time. Be sure to wait about a minute between each addition and scrape down the sides of the bowl to ensure the batter is mixing evenly.
Sift together the salt, flour, and baking powder into a large bowl and set aside. Add the vanilla to the milk.
Slowly add the dry ingredients and wet ingredients to the batter by alternating between the two. Starting with the flour mixture and ending with the milk. Scrape downs the sides of the bowl as you go.
Combine the white chocolate chunks, raspberries, and a tablespoon of flour in a medium bowl. Using a rubber spatula, fold this through the loaf cake batter.
Pour the batter into a prepared loaf pan and bake in a preheated oven for 50 to 55 minutes or until a skewer inserted into the center of the loaf comes out clean.
Allow the loaf to cool in its tin for 40 minutes before turning it onto a wire rack to cool completely. Combine the icing sugar and water together and drizzle this over the cooled loaf cake. Decorate with raspberries, and enjoy!