In a large bowl mix together the butter, brown sugar, and white sugar until smooth and light.
Add eggs one at a time, mixing after each addition. Add the vanilla.
In a separate bowl combine the dry ingredients: salt, baking soda, baking powder, flour, rolled oats, cinnamon, and 1 cup of chocolate chips.
Add to the wet ingredients and mix until combined. Spread 1/2 of the cookie dough into the bottom of a lightly greased 9 x 13 inch baking pan. Sprinkle remaining chocolate chips on top, adding a handful more if necessary.
Add remaining cookie mixture on top of chocolate and lightly press down and smooth out with the back of a greased spoon.
Bake for 25 to 30 minutes at 350 degrees or until golden brown. Allow to cool completely before cutting and serving.