Combine oatmeal, cake flour, baking powder, and salt in a bowl.
In a separate bowl, mix butter and sugar together until creamy.
Add the egg and blend well.
Add the dry ingredients to the butter mixture and mix evenly.
Fold in chocolate chips and nuts evenly.
Shape the dough into rounds and place them on a baking pan.
Bake in a preheated oven at 180°C (356°F) for 12–15 minutes.