Preheat oven to 350°F. Lightly grease two cookie sheets and set aside.

Beat butter, sugar, and brown sugar together on medium speed until smooth and creamy. Add eggs and vanilla and mix until well combined.

In a separate bowl, mix together the flour, baking soda, salt, and cinnamon, then add to the butter mixture and beat until combined. Stir in oats and chocolate chips.

Scoop dough into rounded tablespoons and place on baking sheets about 2 inches apart. Lightly press down to flatten each dough ball. Bake for 9-11 minutes, or until done. For chewier cookies, bake for 9 minutes, for crispier baker for 11 minutes.