In a large bowl with an electric mixer, beat the butter and sugar until combined, about 1 minute.
Add the eggs and egg yolks, one at a time, beating until combined and scraping down the edges of the bowl as needed.
Add the pumpkin puree and beat until combined. The mixture might be a little lumpy - that's okay.
Add the pumpkin pie spice, baking powder, baking soda, and salt, and mix to combine.
Add the cake mix and flour beating until combined.
Chill for 30-60 minutes.
Preheat the oven to 325 degrees F.
Form the dough into ½ cup dough balls. Yes - these are BIG cookies!
Place 3 on a parchment paper lined baking sheet.
Bake in the preheated oven for 14-16 minutes. The edges will be slightly golden and the tops should no longer appear "wet." If they still appear wet, bake for an additional 1-3 minutes. They will still be very soft - but will firm up as they cool.
Cool for 10-15 minutes before transferring them to a wire rack to cool completely.