Prep. Preheat the oven to 375°F. Line a muffin pan with liners or spray with nonstick spray.
Dry ingredients. In a large bowl, whisk 1 3/4 cups flour, 1 cup sugar, 1 1/2 teaspoons pumpkin pie spice, 1 teaspoon cinnamon, 1 teaspoon baking soda, 1 teaspoon baking powder, and 3/4 teaspoon salt.
Wet ingredients. Stir in 1 cup pumpkin puree, 1/4 cup oil, 1/4 cup applesauce, 2 eggs, and 1 1/2 teaspoons vanilla and mix just until combined. Do not overmix. Fold in the 1 cup chocolate chips.
Add batter to pan. Using a large cookie or ice cream scoop, scoop the batter into muffin pan, filling the liners 3/4 the way full. Press extra chocolate chips on top, if desired.
Bake. Bake 20 to 22 minutes, or until a toothpick inserted into the center comes out clean. Remove from oven and let cool on a cooling rack.
Notes
Freezer instructions: Allow to cool and then place in a zip top bag or freezer container (release as much air as possible). Then place in the freezer for up to 3 months. Set out to thaw and then microwave for a few seconds. Storage: Store the muffins in an airtight container for up to 3 days at room temperature.