Preheat oven to 375. Line a 12-cup muffin pan with cupcake liners.
In a large bowl combine flours, pumpkin pie spice, baking powder, baking soda and salt. Set aside.
In a medium bowl whisk together pumpkin, yogurt, maple syrup, butter, egg and vanilla. Stir in carrots. Add wet ingredients to dry ingredients and stir until just moistened. Fold in chocolate chips and nuts (if using).
Divide batter evenly among 12 muffin cups (they will be full). Bake for 20-22 minutes or until a toothpick comes out clean.
Cool on a wire rack.
If you don't have pumpkin pie spice, use 1 1/2 tsp. cinnamon, 1/4 tsp. ground ginger and 1/4 tsp. ground nutmeg.