Preheat oven to 350F. Use the remaining butter on the wrapper to grease your loaf tin on the skinny sides, then add a parchment paper sling with an overhang on either broad side to help you lift the loaf out of the tin.
Using a hand or stand mixer, cream the butter and sugar together.
Add the almond and vanilla extracts plus the Greek yogurt, mixing to combine. Be sure to scrape down the sides of the bowl for full incorporation. The batter will look a little curdled at this point.
In a small bowl, mix together the flour, baking powder, and salt.
Add the dry ingredients to the wet ingredients, mixing until no pockets of flour remain. The dough will be quite thick.
Fold in the white chocolate chips.
Using a spoon or damp fingers, add a few dollops of dough to the prepared pan, using damp fingers to help spread it out over the bottom. Sprinkle in about ⅓ of the raspberries. Add more dollops of dough and more raspberries, repeating until all the dough and berries are used up. TIP: Try to end with a few dollops of dough on top so the raspberries don't get too dried out during baking.
Bake in preheated oven for 38-48 minutes, until a toothpick comes out clean. Remove the cake from the oven, allowing it to cool for about 10 minutes in the tin before moving it to a cooling rack to cool completely.