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.
Notes
If you don't have buttermilk - or just don't want to buy a carton especially for this recipe you can make your own. We need ¾ cup of buttermilk - so take ¾ cup full cream milk & add 3 teaspoon lemon juice or white vinegar, mix, and let sit at room temperature for 5-10 mins. By then you should have curdled, chunky looking milk - buttermilk. Just mix and use. If you want 1 cup - then 4 teaspoon (1 tbsp).You can also use other substitutes for buttermilk, I found some here at The Kitchn - full disclosure though I haven't tried any of these other substitutes but I have made my own with lemon juice and with vinegar (it depends what I have on hand).These don't take long to overcook because they are so small, so you really need to be careful with your oven time.My mini muffin tin is 2 tbsp. capacity and is non-stick. If yours isn't non-stick you will need to spray your tin with non-stick cooking spray.*Please note that the amount of calories per serve is provided as a guide only, as ingredients and cooking methods can vary greatly*