Preheat oven to 190 C / Gas 5. Lightly grease 2 large baking tray with vegetable margarine, butter or oil.
Cream the butter and sugars together in a large bowl. Beat in the egg and vanilla extract until well blended. Sieve together the flour, bicarbonate of soda and salt; gradually blend into the batter. Stir in the chopped macadamia nuts and chocolate chips. Drop by rounded teaspoonfuls onto the cookie sheets, about 5cm apart.
Bake in preheated oven for 10 to 12 minutes or until the cookies are golden brown. Remove from the oven and transfer the cookies to cooling racks.
Use white or milk chocolate chips if you wish.
Make a double batch, drop the batter onto baking trays and place in the freezer. Once frozen, place them into a freezer bag and store in the freezer. When you want fresh cookies, cook from frozen, adding 3-5 minutes on to the cooking time.