Use an electric mixer to cream the butter, add white and brown sugar, and mix until smooth and creamy. It is essential to achieve a soft cream before following the next step. Add both eggs, one at a time, mixing very well after each addition. Next, add vanilla extract and mix to combine.
Cover the bowl in film paper and let it chill in the fridge for at least 2 hours. The chilling process is key to the flavor and chewiness of the cookies. If possible, refrigerate it overnight. Before baking the cookies, preheat the oven to 350F and prepare two baking trays with baking paper.