Preheat your oven to 350 degrees. Line baking sheets with parchment paper and set aside.
In a medium bowl whisk together flour, baking soda, salt, and ground cinnamon. Set aside.
In a large bowl, beat together the butter and peanut butter until smooth.
Add the granulated sugar and brown sugar and beat until the batter is light and fluffy. Between 3 to 6 minutes.
Add in the pumpkin, egg yolk, and vanilla extract. Beat until just combined.
Add in the flour mixture and beat on low until it is integrated, turning up the hand mixer and beating until just fully combined.
Using a cookie scoop, create one inch balls. Place on cookie sheet, approximately two inches apart, and using a fork push down one way and then turn the fork pushing down the other way making a hatch mark pattern.
Bake for 12 minutes, rotating half way through. The edges of the cookies should be golden brown.