Preheat the oven to 350 degree. Line your muffin tin with cupcake liners.
Whisk together the water and flax seed for your flax egg. Let it sit for a few minutes to thicken.
In a large mixing bowl, beat together the wet ingredients. Beat until combined and fluffy.
Add in the dry ingredients and beat until fluffy. Your batter will be thicker than an average cupcake batter due to the pumpkin fiber.
Fill the muffin cups.
Bake at 350 degrees for 18-25 minutes. You want the tops to be fluffy yet firm and sturdy to touch upon removing from the oven.
Let them cool for a few minutes in the tin, then remove and let them cool on the counter. You can make your frosting now and place it in the fridge to chill, or wait until the cupcakes are fully cooled and then make the frosting and add right away.
Frost the cupcakes, add some pumpkin spice on top, and serve! Store leftovers in the fridge, covered. Best if eaten within a few days.