Preheat your oven to 325°F. Light coat a 12-inch standard muffin tin with nonstick spray.
In a large mixing bowl, whisk together the oil, honey, and Greek yogurt. Once blended, whisk in the egg and vanilla. Make sure the ingredients are smooth and well blended.
Whisk in the pumpkin purée.
Sprinkle the baking soda, cinnamon, nutmeg, ginger, allspice, and salt over the top. Whisk or use a rubber spatula to stir gently to combine.
Sprinkle the flour and oats over the top, then with a rubber spatula, gently incorporate, just until the flour disappears.
Scoop the batter into the prepared muffin cups, dividing it evenly. The cups will be very full. If desired, sprinkle on a few oats on top for decoration.
Bake for 24 to 29 minutes, or until a toothpick inserted in the center of a muffin comes out clean.
Place the pan on a wire rack and let cool in the pan for 5 minutes, then with a butter knife, gently loosen the muffins and transfer them to the rack to finish cooling.
