Preheat oven to 350°F. Line an 8x8-inch pan with parchment paper. Set aside.
Add the butter and brown sugar to the bowl of a stand mixer fitted with the paddle attachment. Beat on medium speed until the mixture is light and fluffy, about 2 minutes.
½ cup unsalted butter, ¾ cup brown sugar
Add the egg and vanilla. Mix to combine and scrape down the sides of the bowl as needed.
1 large egg, 1 teaspoon pure vanilla extract
Add the flour and baking soda. Mix just until no large lumps of flour remain.
1¼ cups all-purpose flour, 1 teaspoon baking soda
Gently fold in the chocolate chips.
1 cup chocolate chips
Tightly cover the bowl of cookie dough with plastic wrap and refrigerate while you make the cheesecake layer.
For the Cheesecake Layer
Add the cream cheese and granulated sugar to the bowl of a stand mixer fitted with the paddle attachment. Beat on medium speed until the mixture is smooth, about 1 minute.
24 ounces cream cheese, ¾ cup granulated sugar
Add the sour cream and vanilla and mix to combine.
¼ cup sour cream, 1 teaspoon pure vanilla extract
With the mixer on low speed, add the eggs one at a time. Scrape down the sides of the bowl and mix again to make sure all of the cream cheese has been incorporated.
3 large eggs
To Assemble
Remove the cookie dough from the refrigerator. Transfer ¾ of the cookie dough to the prepared pan and press it into the bottom of the pan. Make sure to spread it out in an even layer.
Pour the cheesecake batter on top of the cookie dough.
Crumble the remaining cookie dough over the top of the cheesecake layer.
Bake for 40-45 minutes, or until the center no longer jiggles when shaken.
Remove the cheesecake from the oven and allow it to cool to room temperature. Once cool, transfer it to the refrigerator and chill for at least 4 hours (overnight is best) before slicing and serving.
Notes
Feel free to add any nuts, candies or sprinkles.
Make sure it cools completely before cutting into bars.
Double the pan size and recipe amounts, if you are serving for a larger crowd.
Storage: Store cheesecake bars in an airtight container in the refrigerator for up to 3 days or in the freezer for up to 2 months.