Preheat the oven to 350 degrees F. Line a 12 cup muffin pan with paper cupcake liners.
In a large bowl, whisk together the all-purpose flour, baking powder, baking soda, salt, and ground cinnamon.
In another large bowl, whisk together the vegetable oil, crushed pineapple, eggs, sugar, and vanilla extract until well combined. Slowly add the flour mixture and beat with an electric hand mixer until just combined, about 2 minutes.
Stir in the shredded or grated carrots, walnuts, and raisins (if using).
Fill the cupcake liners 3/4 full with batter.
Bake in preheated oven for 20-22 minutes or until a toothpick inserted into the center of a muffin comes out clean.
Allow the muffins to cool slightly before serving. Enjoy your Pineapple Carrot Cake Muffins!