For the frosting
Preheat the oven to 180°C, gas mark 4.
Grease and line a 20cm spring-form cake tin.
In a food processor, pulse the carrots, apple and pecans until finely chopped. Add the remaining cake ingredients except the raisins; pulse until fully combined. Then pulse in the raisins.
Smooth into the prepared pan.
Bake for 50 minutes to 1 hour, until a toothpick inserted in the centre comes out mostly clean and the top is dry to the touch.
Cool in the pan for 15 minutes. Run a knife around the cake, unhinge the pan and transfer to a cooling rack. Cool completely.
For the frosting, cream the butter until light and fluffy – for approximately 8 minutes. Add the cream cheese and icing sugar and whip until light.
Fold in the yoghurt, refrigerate until firm enough to spread over the cake.