Preheat oven to 350°F. Grease a muffin tin (or line with paper liners).
In a large bowl, whisk together flours, pumpkin pie spice, baking soda, and salt.
In a medium bowl, whisk together pumpkin pie filling, sugars, oil, milk, eggs, and vanilla until well combined.
Add flour mixture into pumpkin mixture and fold together until batter is just combined. Fold in nuts if using.
Divide batter evenly between muffin wells (using a cookie scoop). Batter will fill just below the brims.
Bake for 28-32 minutes, or until a toothpick inserted in the center comes out clean. Cool muffins in the tin for 10 minutes, then carefully remove and cool completely on a cooling rack.
Notes
Make a double batch because it is easy to do and the muffins freeze great!
If muffin tins are larger than normal, extend bake time to about about 34 minutes
If using batter to make a cake, a 9” round cake pan will bake for about 40 minutes