Preheat oven to 350ºF (~176ºC).
Generously grease two 9-inch baking pans with olive oil.
Add about ¼ cup of flour to each pan and move the pan around, tapping, to get the pan coated with flour. Tap out the excess.
In a large bowl, add granulated sugar, brown sugar, and olive oil. Mix with electric mixer. Add eggs and vanilla and beat well.
Add flour to the bowl and right on top of the flour add in the cinnamon, baking soda, baking powder, and salt. Using a spoon/fork, simply try to mix just the dry ingredients together with a spoon/fork to disperse the ingredients. Then use the electric mixer to incorporate all the ingredients together until just combined. Don’t overbeat.
Use a spatula/large spoon to stir in carrots, walnuts, and raisins.
Pour this batter evenly between both cake pans and put the pans in the oven for 30 minutes or until a fork poked through the middle comes out clean.
Allow cakes to cool completely cool before frosting them so that the frosting doesn’t melt.