Cupcake batter

1. Preheat the oven to 350°F / 180°C and line a cupcake pan with paper liners.
2. Whisk together the flour, baking powder, and salt in a medium bowl.
3. Beat the softened butter and sugar in a large bowl (or stand mixer with whisk attachment) on medium speed for 2–3 minutes, until pale and creamy.
4. Add the eggs and vanilla, then beat on high speed for about 3 minutes, until smooth and fluffy.
5. Fold in the dry ingredients and buttermilk alternately, in batches, using a spatula, just until the batter is smooth.
6. Gently mix in the raspberries, whole or roughly chopped, without overmixing.
7. Fill the cupcake liners about ¾ full.
8. Bake for 15–17 minutes, until lightly golden and a toothpick inserted in the center comes out clean.
9. Cool briefly in the pan, then transfer to a wire rack and let cool completely.

Raspberry compote (filling + puree)

1. Combine the raspberries, sugar, and lemon juice in a saucepan.
2. Cook over medium heat until the mixture starts to boil, then reduce heat and simmer for 10–15 minutes, until thick and jam-like.
3. Blend the compote until smooth, then strain through a fine mesh sieve to remove the seeds.
4. Set aside half for filling the cupcakes and reserve the smooth puree for the frosting.
5. Chill completely before use.

Raspberry mascarpone frosting

1. Place the cold mascarpone, cold heavy cream, powdered sugar, vanilla, and strained raspberry puree in a large bowl.
2. Whip with an electric mixer on medium speed for 2–3 minutes, until thick, smooth, and pipeable.
3. Stop mixing as soon as the frosting holds soft peaks.

Assembly

1. Core the center of each cooled cupcake using a cupcake corer.
2. Fill with raspberry compote.
3. Pipe the raspberry mascarpone frosting on top using a star tip (1B), forming swirls.
4. Decorate with fresh raspberries.
5. Chill for 20–30 minutes before serving for best texture.