Preheat the Oven:
Preheat your oven to 375°F (190°C). Line baking sheets with parchment paper or silicone baking mats.
Combine Dry Ingredients:
In a medium bowl, whisk together the flour, baking soda, salt, and cinnamon. Set aside.
Cream the Butter and Sugars:
In a large bowl, using an electric mixer, cream together the softened butter, granulated sugar, and brown sugar until light and fluffy.
Add Eggs and Vanilla:
Beat in the eggs, one at a time, followed by the vanilla extract, mixing until well incorporated.
Add Dry Ingredients:
Gradually add the flour mixture to the wet ingredients, mixing just until combined.
Stir in Oats and Butterscotch Chips:
Stir in the quick-cooking oats and butterscotch chips by hand until evenly distributed throughout the dough.
Scoop the Cookie Dough:
Drop rounded tablespoonfuls of the cookie dough onto the prepared baking sheets, spacing them about 2 inches apart.
Bake:
Bake in the preheated oven for 8 to 10 minutes, or until the edges are golden brown and the centers appear set.
Be careful not to overbake to keep the cookies chewy.
Cool the Cookies:
Allow the cookies to cool on the baking sheets for 2 minutes before transferring them to wire racks to cool completely.