Mary Berry's carrot and walnut cake with cream cheese icing recipe

INGREDIENTS

• 225 carrots, peeled and coarsely grated
• 250 sunflower oil
• ml large eggs
• 4 light muscovado sugar
• g self-raising flour
• 200 baking powder
• g ground mixed spice
• 300 ground ginger
• g walnuts, shelled and chopped, plus 8 halves to decorate
• 2 butter (room temperature)
• tsp icing sugar
• 1 full-fat cream cheese (room temperature)
• tsp drops of vanilla extract