Add the two quantities of sugar and salt to a bowl and stir to combine
Melt butter in a saucepan, gently stirring until brown and smells nutty and like caramel
Add butter, whole egg and vanilla extract to sugar mixture and whisk together until thickened and paler and whisk leaves a trail
Sift in the flour and bicarb
Combine by folding mixture gently until a dough forms and flour is fully incorporated
Fold in chocolate chunks evenly through the dough
Chill for an hour minimum to 12 hours in fridge
Preheat oven at 170C for at least 30 mins before baking
Either using a cookie scoop or a spoon, roll dough into a ball between hands and place at equal distances apart on a baking tray to allow for spread.
Bake for 15 minutes then remove from oven to rack to cool before eating