Cream together the butter and sugars until smooth. Add eggs one at a time, then vanilla. In a separate bowl, whisk together flour, baking soda, salt, and oats. Combine flour mixture and chocolate chips with butter mixture. Drop by large spoonfuls onto ungreased pans.
Bake at 350˚ for 10-12 minutes or until golden brown (I bake them on sheets lined with parchment paper). Cool on wire rack.
Notes
To make Oatmeal Raisin Cookies substitute raisins for the chocolate chips and add 1 teaspoon of cinnamon.