Preheat the oven to 375 degrees. Line baking sheet with silpat or parchment.
In a medium bowl or using your stand mixer, cream together butter, white sugar, and brown sugar. Beat in eggs one at a time, then stir in vanilla. Combine flour, baking soda, salt, and cinnamon in a separate bowl and stir into the creamed mixture. Mix in oats, chocolate, and nuts.
Use a small or medium cookie scoop and drop dough 2 inches apart on cookie sheet. Flatten each cookie slightly.
Bake for exactly 8 minutes in preheated oven. Allow cookies to cool on baking sheet for 5 minutes before transferring to a wire rack to cool completely.