Preheat oven to 350 degrees F. Line a cupcake pan with paper liners.
In a medium bowl, mix together the flour, baking powder and salt. Set aside.
In the bowl of a stand mixer with the paddle attachment on, beat butter and sugar on medium-high speed for about 5 minutes, until light in color and thick and fluffy.
Scrape down the sides as needed.
Add the eggs, one at a time, beating well with each addition. Add the vanilla and beat to combine.
Reduce speed to medium and the flour mixture in thirds, alternating with the buttermilk, make sure they are well incorporated between each addition. Scrape down the bowl and mix for another 30 seconds until the mixture is smooth.
Divide the batter evenly between the 12 cupcake liners, filling about ⅔ full.
Bake for 20-23 minutes or until the tops spring back or a toothpick inserted in the center comes out clean. Allow to cool in the pan for 5 minutes before transferring to a wire rack to cool fully before frosting.
Using a knife, cut out a cone shape from the center of the cupcake (wider on top and narrow towards the center).
Fill with jam or jelly of your choice and replace the lid.
Frost with peanut butter buttercream, sprinkle with chopped salted peanuts and drizzle with warmed jam.