Preheat your oven to 180 C. Lightly grease two 9″ cake pans with butter.
Whisk together flour, sugar, brown sugar, baking powder, baking soda, cinnamon, nutmeg, cloves, and salt in a large bowl. Add the oil, eggs, and vanilla. Beat well. Fold in the chopped nuts, coconut, and carrots.
Pour the batter into the pans, set on the middle rack of the oven and bake for 45-50 minutes or until the edges have pulled away from the sides, and a skewer inserted into the center comes out clean. Cool on a cake rack.
To prepare the frosting, cream together the cream cheese, sour cream, and butter in a mixing bowl. Slowly sift in the confectioners sugar and beat until the mixture is free of lumps. Stir in the vanilla and lemon juice.
Once the cakes have completely cooled, frost. Sprinkle the top with chopped walnuts if desired.