In a large bowl, stir together the oats, flour, baking soda, baking powder, salt and cinnamon.

In another bowl, blend the butter and sugars with an electric mixer until smooth, about 2 minutes. Add the eggs and continue to beat until fluffy (around 1 ^1/2 mins). Blend in vanilla extract.

Using a wooden spoon, stir the dry mixture into the butter minture one half at a time. Mix in the chocolate chips and walnuts. Refrigerate the dough for 1 or 2 hours.

Preheat the oven to 350 °. Line a large, preferably light colored baking sheet with aluminum foil, then grease the foil.

Using a scant 1/4 cup per cookie, shape the dough into balls and place them on the sheet around 2 inches apart.

Use your fingertips to flatten each ball to 1/3 inch thick. Bake the cookies on the center rack for 13 to 14 minutes, flipping the sheet around halfway through. The cookies should look lightly brown and moist when done.

Cool the cookies on the baking sheet for 2 to 3 minutes then transfer to wire rack

Makes roughly 24 cookies