Preheat the oven to 350°F (175°C) and line two baking sheets with parchment paper or silicone baking mats.

In a large mixing bowl, cream together the softened butter, brown sugar, and granulated sugar with an electric mixer on medium speed for 3 to 4 minutes until light and fluffy.

Beat in the eggs one at a time, then mix in the vanilla extract until combined, scraping down the sides of the bowl as needed.

In a small mixing bowl, whisk together the all-purpose flour, baking soda, ground cinnamon, and salt.

Add the flour mixture to the butter mixture and mix on low speed until just combined, stopping when no white flour streaks remain.

Fold in the rolled oats until evenly distributed throughout the dough.

Using a cookie scoop or rounded tablespoon, drop dough portions onto the prepared baking sheets, spacing them 2 inches apart.

Bake for 18 to 22 minutes, or until the edges are golden brown and the centers look slightly underdone.

Cool the cookies on the baking sheets for 5 minutes before transferring them to a cooling rack to cool completely.