Preheat oven to 425°F (220°C). Line a 12-count muffin tin with paper liners.
In a medium bowl, whisk together flour, baking powder, baking soda, salt, cinnamon, ginger, and nutmeg.
In a large bowl, combine granulated sugar, brown sugar, eggs, vegetable oil, vanilla extract, and crushed pineapple.
Gradually add dry ingredients to wet ingredients, mixing just until combined. Fold in carrots and walnuts.
Spoon batter into muffin liners, filling each about ¾ full.
Bake at 425°F (220°C) for 5 minutes. Reduce temperature to 350°F (175°C) and bake for 15-17 minutes until a toothpick inserted comes out clean.
Cool in the tin for a few minutes, then transfer to a wire rack to cool completely.