In a mixing bowl, combine the softened unsalted butter, granulated sugar, and brown sugar. Use a spoon to mix until the mixture is creamy and well combined. This step is important as it incorporates air into the butter, helping the cookie to rise.

Add the vanilla extract and the beaten egg to the bowl. Mix until fully incorporated. The egg adds moisture and helps bind the ingredients together.

In a separate bowl, whisk together the all-purpose flour, baking soda, and salt. This ensures that the baking soda is evenly distributed throughout the flour.

Gradually add the dry ingredients to the wet mixture, stirring gently until just combined. Be careful not to overmix, as this can make the cookie tough.

Fold in the chocolate chips using a spoon or spatula, ensuring they are evenly distributed throughout the dough.

Preheat your oven to 350°F (175°C). This ensures that the cookie bakes evenly and achieves the desired texture.

Line a small baking sheet with parchment paper. This prevents the cookie from sticking and makes for easy cleanup.

Scoop the cookie dough onto the prepared baking sheet, forming a single large cookie. You can shape it into a round disc about 1/2 inch thick.

Bake in the preheated oven for 8-10 minutes, or until the edges are golden brown and the center is still soft. The cookie will continue to cook slightly after being removed from the oven.

Allow the cookie to cool on the baking sheet for a few minutes before transferring it to a wire rack to cool completely. This helps it set and makes it easier to handle.