Cream together butter, white sugar, brown sugar and peanut butter.
Add egg and vanilla, beating until mixed.
Add flour, baking soda, salt and cinnamon and continue to beat until mixed.
Add oats and chocolate chips, stirring with spoon until equally distributed.
Cover and chill in refrigerator for 1 hour.
Preheat oven to 375 degrees.
Place rolled cookie dough balls on greased baking sheet. Place them 2 inches apart as they will expand. With a fork, press down on each cookie so they flatten out a bit.