Start by making the raspberry reduction. Put raspberries and sugar into a small pot and place over medium heat. Allow simmering until the raspberries have broken down to a sauce (you can help them along by smashing them with a fork).
When the raspberry sauce has reduced by about a third, pour through a sieve to strain the seeds from the sauce.
Place in the fridge to chill. This recipe will make a bit more than you need. You can put the rest of the reduction in the freezer to save for later.
Preheat the oven to 180°C (360°F). Line a cupcake baking tray with muffin liners.
To make the cupcakes start by sifting together the dry ingredients and stir well together.
Add all of the wet ingredients and mix well. Don't overmix the batter.
Fold in the raspberries and pour into cupcake baking tin lined with cupcake liners.
Bake at 180°C for about 20 minutes or until you can stick a toothpick in the middle and it comes out clean. Remove from oven and allow to cool completely.
To make the buttercream, beat the margarine in the mixer until light and fluffy (I prefer to use 1/3 part Trex to 2/3 Stork) but regular margarine will do just fine. Add the icing sugar and continue to beat for a few minutes or until the mix is well combined. Add the vanilla and raspberry reduction and mix well.
Place the buttercream in a piping bag fitted with the 1M piping tip.
When the cupcakes are completely cooled you can pipe on the buttercream. Decorate with a fresh raspberry on top.