Make your flax eggs by combining the flaxseed meal and water and letting it sit for a few minutes until it "gels up"
In a large bowl, beat the butter, nut/seed butter, vanilla, and coconut sugar with an electric mixer on medium speed, scraping bowl occasionally, until well blended
Beat in the pumpkin and flax eggs until well mixed.
On low speed, beat in the flour, baking soda, baking powder, pumpkin pie spice and salt
On ungreased cookie sheets, drop dough by heaping tablespoonfuls OR gently roll the dough between your hands and then lightly flatten them with the palm of your hand (not too flat)
Bake 10 to 12 minutes and cool for about 15-20 minutes before frosting.
For the Frosting
In a medium bowl, place powdered sugar, 1 teaspoon vanilla, cinnamon, and 3 tablespoons plant (non-dairy) milk
In a small saucepan, melt 1/4 cup butter over medium heat, whisking constantly, then add the bourbon (optional)
Pour the melted butter mixture into the powdered sugar bowl and whisk until the powdered sugar is dissolved. If the frosting is too runny, add more powdered sugar, but keep it mind it will set up as it sits. If it's too dry, add just a splash more milk
When the cookies are cool, frost the cookies and sprinkle with cinnamon.
Store in an airtight container for up to 3 days
**NOTE: if you use sunflower seed butter, your cookies will likely turn green as they cool. Google why this happens!