Classic Carrot Cake

I brought this cake into work and got very good comments on it.  It is simple to make and has everything a carrot cake should have, a little spice, moist cake and a light but tasty icing.

CAKE
1 cup canola oil
1 cup granulated sugar
3/4 cup packed brown sugar
4 eggs
2 cups all purpose flour (I always use unbleached)
2 tsp each; cinnamon, baking soda, baking powder
1 tsp salt
3 cups carrots finely grated (approx 454 g)

ICING
1/4 cup butter, softened
1 cup regular or low fat cream cheese, softened
4 cups icing sugar
1 tsp vanilla extract
1 tbsp milk, if necessary

1. Preheat oven to 350F.  Grease two 9" cake pans
2. CAKE: Beat oil and sugars together in a large bowl with an electric mixer until combined.  Add eggs, one at a time, beating well after each addition.
3. Combine flour cinnamon, baking soda, baking powder and salt in a separate large bowl.  Add flour mixture to egg mixture.  Mix just until combined.  Fold in carrots.  Divide batter evenly into prepared pans.  Bake in preheated oven, 30 to 35 minutes or until a toothpick inserted in centre of cake comes out clean.
4. Cool in pans, 20 minutes.  Remove and cool completely on wire cooling rack.
5. ICING: cream butter and cream cheese in a large bowl of an electric mixer.  Add icing sugar, 1 cup at a time.  Beat well after each addition.  Add vanilla.  Continue beating until fluffy.  Add 1 tbsp milk at a time to thin out icing if necessary.
6. ASSEMBLY:  Place one cake on serving dish.  Spread with icing. Top with remaining cake layer.  Spread top with remaining icing.