Preheat your oven to 375°F (190°C) and line a baking sheet with parchment paper.

Cream together the softened unsalted butter, brown sugar, and granulated sugar until light and fluffy.

Beat in the eggs, one at a time, and then add the vanilla extract until well combined.

Whisk together the flour, baking soda, salt, and cornstarch in a separate bowl, then gradually mix into the wet ingredients until just combined.

Fold in the milk chocolate chips until evenly distributed throughout the dough.

Scoop out the dough onto the prepared baking sheets, leaving enough space between each cookie.

Bake the cookies for 10-11 minutes until the edges are golden and the centers are soft.

Cool the cookies on the baking sheet for 5 minutes before transferring them to a wire rack to cool completely.