In a large bowl, whisk buttermilk, pumpkin, eggs, oil, and vanilla until well-combined.
Add flour, sugar, baking soda, pumpkin pie spice, and salt. Whisk just until incorporated. Don't overmix.
Let batter rest for about 5 minutes.
Heat a griddle or skillet and grease with butter.
Scoop 1/3 cup batter and pour into the griddle.
The pancakes are ready to flip when the edges look dry and set and bubbles form and begin to pop, 1-3 minutes.
Flip and cook on the other side until golden brown and completely cooked through, 1-3 more minutes.
Notes
Buttermilk: Regular or low-fat will work.
Oil: Oils such as vegetable, canola, olive, or melted coconut oil will work. If using melted coconut oil, be sure to have your buttermilk and eggs at room temperature.
Flour: Be sure to properly measure the flour by stirring it to break it up, lightly spooning it into the measuring cup, and then leveling it off.
Pumpkin spice: If you want stronger pumpkin spice flavor, use 1.5-2 tablespoons of pumpkin pie spice.