In a large mixing bowl, cream together the butter and sugars.
Beat in the eggs, one at a time and then mix in the vanilla
In a separate bowl mix the flour, baking soda, and salt together, then add it to the cream mixture. Stir until just combined.
Mix in the oats, walnuts and chocolate chips. Once combined drop the dough, by heaping spoonfuls, onto UNgreased cookies sheets.
Bake for 10-12 minutes and then allow them to cool for another 5 minutes on the cookie sheet. (this will help them bake a little longer as well) Then transfer them to a wire rack to finish cooling off.
You should be able to get about 3 dozen depending on the size.