Prepare the Oven and Baking Sheets:

Preheat your oven to 350°F (175°C). Line baking sheets with parchment paper or silicone baking mats.

Cream Butter, Cream Cheese, and Sugars:

In a large mixing bowl, beat the butter, cream cheese, brown sugar, and granulated sugar together using a mixer on medium speed until light and fluffy, about 2-3 minutes.

Add Egg and Vanilla:

Beat in the egg and vanilla extract until well combined.

Combine Dry Ingredients:

In a separate bowl, whisk together the flour, cornstarch, baking soda, and salt.

Mix Wet and Dry Ingredients:

Gradually add the dry ingredients to the wet ingredients, mixing on low speed until just combined. Avoid overmixing.

Fold in Chocolate Chips:

Using a spatula, gently fold in the chocolate chips until evenly distributed.

Scoop the Dough:

Scoop the dough into 2-tablespoon-sized balls and place them on the prepared baking sheets, spacing them about 2 inches apart.

Bake the Cookies:

Bake for 9-11 minutes, or until the edges are set but the centers still look slightly underbaked. This ensures a soft texture.

Cool the Cookies:

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