Pre-heat oven to 350 degrees F. Line cupcake tins with paper liners
In mixer on low speed, combine sugar and butter until well mixed, scraping down the sides of the bowl occasionally, about 5 minutes.
In a large bowl combine dry ingredients, baking powder, spices, salt and flours
In a separate bowl, whisk together the vanilla and egg whites. Stir the pumpkin puree into the whites just until incorporated.
Add the dry ingredients and the pumpkin mixture to the egg and butter mixture, using about 1/3 of each mixture, and mixing each time, just until incorporated. Mixture should be blended and even in color.
Fold in chocolate chips.
Fill cupcake liners 3/4 full. Bake at 350 degrees F. for 10-12 minutes or until toothpick inserted in middle comes out clean.
Transfer to wire rack and cool.
Frost with Cream Cheese Frosting.