In a large bowl, whisk the flour, baking soda, cornstarch, and salt together. Set aside. 2 ¼ cups (280 g) all-purpose flour 1 teaspoon baking soda 2 teaspoons cornstarch ½ teaspoon salt
In a medium bowl, whisk the melted butter, brown sugar, and granulated sugar together until no brown sugar lumps remain. ¾ cup (170 g) unsalted butter ¾ cup (150 g) packed light brown sugar ½ cup (100 g) granulated sugar
Whisk in the egg and egg yolk until evenly mixed in. Whisk in the vanilla extract until evenly incorporated. 1 large egg + 1 egg yolk 2 teaspoons pure vanilla extract
With a spatula or wooden spoon, stir in the flour mixture and the chocolate chips. Let the dough sit for 10 minutes to thicken up before scooping. 1 ½ cup (255 g) semi-sweet chocolate chips
Scoop the cookie dough in 3 Tablespoon amounts (about 60 g). Flatten each cookie dough ball and place a cheesecake center in the middle of the cookie dough. Fold the cookie dough around the cheesecake center. Place the cookie dough balls on a wax paper or parchment lined baking sheet. Cover and refrigerate for at least 2 hours.
When ready to bake, preheat oven to 350°F (180°C). Line large baking sheets with parchment paper or silicone baking mat.
Place 6-8 cookies spaced about 3 inches apart. Bake the cookies for 12-14 minutes or until the edges are very lightly browned. The centers will look soft but will continue to set up. When you remove the cookies I like place a few extra chocolate chips on top. Cool on the baking sheet for 10 minutes. After 10 minutes of cooling on the baking sheets, transfer cookies to a wire rack to cool completely. Cookies stay fresh covered at room temperature for up to 1 week.