Start by gathering all the ingredients. Preheat your oven to 350°F (175°C), and prepare a 9x13-inch baking pan by greasing and flouring it thoroughly.

To make the cake: In a large mixing bowl, combine the flour, ground cinnamon, baking soda, baking powder, and salt. Create a well in the center of the dry ingredients and add the sugar, vegetable oil, eggs, and vanilla extract. Using a wooden spoon, mix everything together until the batter is smooth. Fold in the shredded carrots, flaked coconut, chopped walnuts, and drained crushed pineapple until evenly combined. Pour the batter into the prepared baking pan and spread it out evenly.

Bake in the preheated oven for approximately 45 minutes, or until a toothpick inserted into the center of the cake comes out clean. Remove the cake from the oven and let it cool completely in the pan. Note that the center of the cake may sink slightly as it cools, which is normal.

To make the frosting: In a mixing bowl, beat the cream cheese and softened butter together until the mixture is smooth and well blended. Gradually add the confectioners' sugar and continue beating until the frosting becomes creamy and spreadable. Once the cake is completely cooled, spread the frosting evenly over the top. Cut into squares and serve.