Pre heat oven to 180c.
In a large high-sided bowl, combine egg, butter, sugar & vanilla. Beat with an electric mixer for 4 mins or until light and fluffy - you will need to scrape down the sides of the bowl as you go.
Add buttermilk & mix by hand until just combined.
Fold in remaining dry ingredients until incorporated - don't over mix.
Take a 24 hole (see note) mini muffin tin and divide batter evenly amongst holes - about 3 teaspoons in each.
Place one whole raspberry on top of each muffin, point facing down, pressing down lightly to indent into batter.
Fill inside of each raspberry with jam.
Bake for 9 mins.