Preheat your oven to 350°F (175°C). Line a muffin tin with paper liners.
In a large bowl, whisk together the pumpkin puree, vegetable oil, sugar, eggs, and vanilla extract until smooth.
In another bowl, mix the flour, baking powder, baking soda, salt, and chai spice mix.
Gradually add the dry ingredients to the wet ingredients, stirring until just combined.
Divide the batter evenly among the muffin cups.
Bake for 20 minutes or until a toothpick inserted into the center comes out clean.
Let the muffins cool in the tin for 5 minutes, then transfer to a wire rack to cool completely.