The ultimate makeover: Carrot cake

Name: The ultimate makeover: Carrot cake
Ingredients: 1 medium orange; 140g raisin; 125ml rapeseed oil; 115g plain wholemeal flour; 1 tsp baking powder, plus a pinch; 1 tsp bicarbonate of soda; 1 rounded tsp ground cinnamon; 140g dark muscovado sugar; 280g finely grated carrot (about 375-400g carrots before peeling); 2 eggs; 115g self-raising flour; 100g light soft cheese, straight from the fridge; 100g Quark; 3 tbsp sifted icing sugar; ½ tsp finely grated orange zest; 1 ½ tsp lemon juice