Preheat oven to 350°F and grease a 12-cup muffin tin.
Mix the milk and vinegar in a small bowl and set aside.
Mix the flour, salt, baking soda, baking powder, pumpkin pie spice, sugar and brown sugar in a large mixing bowl.
Stir in the pumpkin purée, oil, vanilla and milk mixture.
Stir in the chocolate chips.
Evenly distribute the batter into the muffin tin, filling all 12 cavities.
Bake for 20-24 minutes, until a toothpick comes out clean or with only crumbs.
Allow to cool slightly and serve! These are delicious plain or with a bit of vegan butter or pumpkin butter.