Preheat the oven to 375F and grease a 9 x 13-inch baking dish with high sides.
In a large mixing bowl use a whisk to mix the flour, baking powder, salt, and spices.
In another smaller mixing bowl crack in the eggs, then pour in the oil, both sugars, and vanilla extract. Whisk it all together until it is well combined.
Add the wet mixture to the dry mixture and whisk it all together. It will be quite stiff. Then add in the carrots, pineapple, and chopped walnuts and combine. You will see that the mixture gets runnier as you go as the liquid in the carrots and pineapple mixes into the batter.