Whisk the flour, baking powder, pumpkin pie spice, cinnamon, and salt together in a large mixing bowl.
In a separate container, stir together the milk, pumpkin puree, brown sugar, oil, and vanilla.
Add the milk mixture to the bowl with the flour mixture. Whisk the batter until completely combined.
Lightly oil the bottom of a medium skillet (Note 2). Place it over medium heat. Give the oil a minute to heat up, then drop the batter on the hot skillet, using about ⅓ cup per pancake. You can cook multiple pancakes at a time if they'll fit, as long as you avoid crowding the skillet.
Once you see bubbles forming in the center of a pancake, after about four minutes, you can test it out to see if it's ready to flip. Gently place a spatula under an edge of the pancake. If it feels stable, flip it. Cook each pancake for two or thee more minutes after flipping.
If possible, serve the pancakes immediately after they come out of the pan. If not, place them on a wire rack until ready to serve.
Transfer the pancakes to plates and top them with toppings of choice. Serve.