Step 1: Cream the softened unsalted butter with the light brown sugar and caster sugar in a large mixing bowl until pale, fluffy, and smooth, approximately 3–4 minutes on medium speed.
Step 2: Add the egg and vanilla extract. Beat on low speed until fully combined. Scrape down the sides of the bowl.
Step 3: In a separate bowl, whisk together the plain flour, baking soda, and salt until evenly distributed.
Step 4: Add the dry ingredients to the wet mixture in two batches, folding gently with a spatula or mixing on the lowest speed. Stop as soon as no dry flour is visible. Do not overmix.
Step 5: Fold in 200g of chocolate chips by hand using a spatula.
Step 6: Portion the dough into balls of approximately 60–70g each. Place on a parchment-lined baking tray with at least 5cm spacing. Chill in the refrigerator for a minimum of 30 minutes.
Step 7: Preheat the oven to 180°C fan (350°F) or 200°C conventional. Bake for 10–12 minutes until edges are golden but centres still appear soft and slightly pale.
Step 8: Remove from the oven and let cookies rest on the baking tray for 5 minutes before transferring to a wire rack to cool further.
