Preheat the oven to 350°F (175°C). Grease two 9-inch round cake pans or a single 9x13-inch baking dish.

In a large bowl, whisk together flour, baking powder, baking soda, cinnamon, nutmeg, and salt.

In another bowl, mix granulated sugar, brown sugar, and vegetable oil until smooth. Add eggs one at a time, whisking well.

Fold the dry mixture into the wet ingredients until just combined.

Gently fold in grated carrots, drained crushed pineapple, and shredded coconut (if using).

Pour batter into prepared pans and bake for 30-35 minutes until a toothpick comes out clean.

Once baked, cool cakes in pans for 10-15 minutes then transfer to a wire rack to cool completely.

In a mixing bowl, beat cream cheese and butter until fluffy. Gradually add powdered sugar, vanilla, and milk/juice until smooth.

Frost the cooled cakes and garnish with toasted coconut or chopped nuts.