Preheat the oven to 180'C.
Whisk together the butter and the sugar. When light in colour and fluffy in texture slowly add the eggs one by one. When all of the eggs are incorporated, slowly sift the self raising flour and baking powder into the butter mixture. Fold the mixture very gently with a spatula. Ensure all of the flour is mixed in well. Finally add the olive oil to the mixture. Pour the mixture into a piping bag. Pipe the mix into the cupcake cases 3/4 of the way full.
Place in the oven for 12 minutes. Remove from the oven and allow to cool before decorating.
Mix the chopped pistachio nuts and the natural yoghurt together.
Whisk the icing sugar, pistachio paste, food colouring and the butter together until light in colour and fluffy. Place the icing into a piping bag with a star nozzle and set aside.
Place the caster sugar in a deep pan on a medium heat. Roll and tilt the pan until the sugar is completely melted. Increase the heat and rapidly boil until the sugar is golden brown. This should take about 5 minutes. Remove the pan from the heat.
Place the pistachios on a cocktail stick and dip into the caramel. Pull out and allow any excess caramel to drip off. Lay the dipped pistachios onto a sheet of grease proof paper and allow to cool.
Remove a small part of the centre of the cupcake with a teaspoon. Fill the hole with the yoghurt and nut mix.
Pipe the icing on top of the cake starting from the outside of the cupcake and working your way in. Finish the cupcakes with the caramelised pistachios.
«When using olive oil in a cake, always add it last to prevent the cake mix from splitting. »