Preheat oven to 350ᵒF/177ᵒC. Grease and line a cookie sheet. Set aside.

Cream butter until soft and fluffy. Add sugars and continue beating until smooth and lighter in color. Beat in egg and vanilla.

Sift dry ingredients together and add to the creamed mixture. Stir in chocolate chips, nuts and cornflakes.

Scoop out cookie dough into the prepared pan. Bake for 12-15 minutes or until lightly browned and set but still soft in the center.

Remove from the oven. Cool in the pan for a few minutes then place on a wire rack to cool completely.

Serve