In a medium bowl whisk the flour, cinnamon, baking soda, and salt together. Set aside.
In the bowl of your stand mixer fitted with the paddle attachment, beat the butter until smooth, about 1 minute. Add the brown sugar and granulated sugar and beat on medium speed until well creamed, about 2-3 minutes.
Add the eggs, vanilla, and molasses to the creamed butter and sugar. Beat on medium-high speed until well combined. Scrape down the bowl with a spatula as needed so that everything is evenly incorporated.
Add the dry ingredients to the wet ingredients. Beat on low speed until everything is combined.
Add the oats and chocolate chips. Mix until evenly combined. Dough will be thick.
Cover and chill the dough for at least 1 hour.
Preheat the oven to 375°F. Line baking sheets with silicone baking mats or parchment paper.
Using a 3 tablespoon cookie scoop, scoop balls of dough onto the parchment paper, leaving 2 inches between each cookie.
Bake cookies for 9-13 minutes or until lightly browned on the sides. Take note, the centers will still look fairly soft. (In my oven, my cookies are done at 10 minutes).
Remove cookies from the oven and allow them to cool on the baking sheet for 5 minutes before transferring to a wire rack to cool completely. Cookies can be stored in an airtight container for 5 days, if they last that long :)
*You can use a 2 Tablespoon cookie scoop as well, but just know that the cookies won't need to bake for as long.Recipe Source: adapted from Sally's Baking Addiction