Note - if you have time to chill your dough after making, prior to baking, for at least an hour, that's great. If not your cookies will still be great, but chilling the dough up to 24 hours before baking is always a great option, just store tightly covered in the fridge after it's all mixed, up!
Preheat oven to 325 degrees F.
In a large bowl, cream together butter and sugars until light and fluffy, at least 2-3 minutes, using a stand mixer or electric mixer.
Beat in eggs and vanilla. Mix until well combined.
In a separate bowl, combine flour, baking soda, salt, cinnamon and oats. Stir until well mixed.
Combine the dry mixture, with the wet mixture, and stir until just combined. Fold in butterscotch chips.
Line baking sheets with parchment paper or a silicone baking mat. Using a large cookie scoop, drop scoopfuls of dough onto baking sheet, at least 2" apart.
Bake for approximately 10 minutes, remove from oven and allow cookies to cool on sheets for at least five minutes or longer. Transfer to a wire rack to allow to cool completely. Store in an airtight container. Enjoy!