Beat the butter, vanilla essence and sugars in a large bowl with electric mixers until light and fluffy.
Add the egg and beat until well combined.
Mix in the flour and choc chips with a spoon, until the mixture has just come together.
Place the cookie dough in a large Q Ware fry pan and press down to evenly spread.
Cover and refrigerate for an hour or until firm.
Preheat barbecue for indirect cooking. On a Weber Q use a convection tray and trivet.
Once the barbecue is preheated, set the control knobs to the roast setting. Place the Q Ware Fry Pan in the center of the grill, ensuring handle is removed.
Bake the cookie for 12 to 14 minutes or until lightly golden. Remove from the barbecue using the detachable handle.
Allow to cool for at least 5 minutes on a cake cooling rack.
Serve with vanilla ice cream.