Prepare your cupcake tin by lining it with muffin liners and preheat your oven to 175℃ / 347℉ (no fan).

In a large bowl, cream the room-temperature butter and sugar for a few minutes until it's light and fluffy.

Then, whip in the room-temperature eggs in slowly, followed by the vanilla extract.

Slowly pour the room-temperature milk into the mixture as you keep whipping the batter.

Sift in the flour, baking powder, and salt over the batter. Then, switch to a rubber spatula and fold in the dry ingredients carefully, not overmixing the batter at this point.

In a small bowl, mix vinegar with the baking soda. It will be super bubbly. Then, immediately fold the vinegar mixture into the batter just until it's combined.

Pipe or spoon the batter evenly into the cavities of your cupcake tin, filling each one about ¾ full.

Bake the cupcake for about 20-22 minutes or until a toothpick inserted into the center comes out clean. Do not overbake them, as they can dry out.

Cool the baked cupcakes on a cooling rack. They must be at room temperature before frosting.

Cook all the ingredients for about 10 minutes until slightly thickens. Let it cool before using it. Alternatively, you can use raspberry jam instead.

Place the finely chopped chocolate in a medium heat-proof bowl and semi-melt in the microwave. Let it come to room temperature before using (but do not wait until it sets).

Using your stand mixer or electric hand mixer, cream the room-temperature butter at medium-high speed for 3 minutes until it becomes light in color and fluffy in texture.

Add in the powdered sugar tablespoon by tablespoon on low speed, then turn the mixer back on medium-high speed and whip it for another 4 minutes or until the mixture becomes light, fluffy, and increases in volume.

Now, add the melted white chocolate to the buttercream slowly while the mixer is on.

Lastly, add the vanilla extract, salt, and heavy cream and continue whipping for another minute until it is smooth and silky.

Then, once the frosting is ready, switch to a rubber spatula and loosely fold in the raspberry reduction. Do not fully mix the reduction into the frosting, if you want to achieve a marbled effect on the frosting.

Move the white chocolate frosting into a piping bag fitted with a piping nozzle.

Make a small hole in each of the cupcakes and fill them with about ½ tablespoon of raspberry sauce each.

Then, frost the cupcakes with the white chocolate raspberry frosting and decorate according to your liking with fresh raspberries, chocolate shavings, or herbs like mint.

The cupcakes are best served fresh. Any leftovers can be stored refrigerated for 2-3 days in an air-tight container. Bring them back to room temperature before serving for the frosting to soften.