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

In a large bowl, whisk together the cake flour, baking powder, baking soda, and ground cinnamon.

In another bowl, cream the butter with granulated sugar and brown sugar until light and fluffy.

Add the vegetable oil, eggs, milk, and vanilla extract to the butter mixture, mixing until well incorporated.

Gradually add the dry ingredients to the wet ingredients and mix gently, then fold in shredded carrots and crushed pineapple.

Pour the batter into the prepared pans and bake for approximately 36 minutes until a toothpick comes out clean.

While the cakes cool, prepare the frosting by beating together cream cheese and unsalted butter until smooth, then add powdered sugar and pineapple juice.

Once the cakes are cooled, assemble by placing one layer on a plate, adding frosting, and topping with the second layer, then frosting the top and sides.

Top with chopped pecans if desired for a crunchy finish.