Prepare your equipment and ingredients. Preheat your waffle iron according to manufacturer’s instructions. Measure out all ingredients and have them ready at your workspace.
Mix the dry ingredients thoroughly. In a large bowl, whisk together the flour, baking powder, sugar, salt, and pumpkin pie spice until well combined and no lumps remain.
Combine the wet ingredients separately. In a medium bowl, whisk the pumpkin puree, plant milk, oil, apple cider vinegar, and vanilla extract until smooth and uniform in color.
Create the batter by combining both mixtures. Pour the wet ingredients into the dry ingredients and stir just until combined. Some small lumps are okay – overmixing will make your waffles tough instead of fluffy.
Let the batter rest briefly. Allow the mixture to sit for 5 minutes while your waffle iron fully heats. This gives the baking powder time to activate and the flour to properly hydrate.
Cook the waffles to golden perfection. Lightly grease your preheated waffle iron (even if it’s non-stick). Pour approximately ½ cup of batter into the center of the iron (amount will vary based on your waffle maker size). Close the lid and cook until steam stops escaping and the waffle is golden brown, about 4-5 minutes.
Keep waffles warm while cooking the remaining batter. Place cooked waffles directly on the rack in a 200°F oven to stay crisp while you finish cooking the remaining batter.
Serve immediately with your favorite toppings. These waffles pair beautifully with maple syrup, a dollop of vegan butter, fresh fruit, or a sprinkle of chopped nuts.