Preheat your oven to 350°F (175°C) and grease two 9-inch round cake pans.

In a large mixing bowl, combine vegetable oil, granulated sugar, brown sugar, and eggs. Whisk until smooth, then stir in vanilla extract.

Fold in the finely grated carrots and the well-drained crushed pineapple until evenly mixed.

Sift together flour, baking soda, baking powder, salt, and cinnamon in another bowl.

Gradually fold the dry ingredients into the wet mixture until just combined.

Divide the batter between the prepared pans and smooth the tops. Bake for 25-30 minutes until a toothpick comes out clean.

Allow cakes to cool in the pans for 10 minutes, then transfer to wire racks to cool completely.

Frost with cream cheese frosting and decorate with chopped walnuts or coconut as desired.