Preheat the oven to 350 degrees.
In a large mixing bowl combine cake mix, eggs, pumpkin puree, and vanilla and mix well with a fork (or you could use a hand or stand mixer).
Create heaping 1 tablespoon cookie dough balls with a cookie scoop or spoon and place them about 2 inches apart on a baking sheet that has been lined with parchment paper (dough will be wet and sticky).
Gently pat down the cookie dough balls (but no need to roll them into a ball).
Bake for 9-10 minutes.
Remove from the oven and let cool on the baking sheet for 5 minutes before transferring to a cooling rack.
While the cookies cool, make the frosting.
Using a hand mixer, beat cream cheese and butter together on low in a medium-sized mixing bowl until there are no clumps.
Add powdered sugar, vanilla, and 1/4 teaspoon cinnamon and beat well.
Spoon frosting onto cookies and sprinkle with remaining cinnamon (optional).