Preheat oven to 350°F (177°C). Line a mini muffin tin with paper liners or coat with non-stick cooking spray.
In a medium bowl, whisk together the flour, baking soda, baking powder, salt, and pumpkin pie spice.
In a large bowl, whisk together pumpkin puree, vegetable oil, milk, granulated sugar, brown sugar, egg, and vanilla extract until smooth.
Add the dry ingredients to the wet mixture and gently fold until just combined. Do not overmix.
Scoop the batter into the muffin cups, filling each about ¾ full (approximately 26g per muffin).
Bake for 13–16 minutes, or until the tops spring back when lightly pressed and a toothpick inserted comes out clean.
Cool in the pan for 5 minutes, then transfer to a wire rack to cool completely.
To glaze, spoon a small dollop of cinnamon glaze onto each muffin and use the back of a teaspoon to spread it gently. Adjust glaze consistency with a few drops of water if needed.