Preheat the oven to 350℉. Line a 9x9-inch baking pan with parchment paper or spray with cooking spray. Set aside for now. * I like to spray the pan with cooking spray and then press parchment paper into it. The spray helps the paper adhere to the pan and not move as much. In a mixing bowl add the chocolate chip cookie mix and chocolate chips. Stir together to combine.
1 package (17.5 oz) chocolate chip cookie mix, 1/4 cup chocolate chips
Pour in the melted butter and egg. Stir until thoroughly combined and it forms a thicker batter. * It might be easier to mix this with an electric hand mixer, if wanted. 1/2 cup (1 stick) salted butter, 1 large egg
Press a little over half of the cookie dough into the prepared pan. Use lightly floured fingers to avoid sticking. Set the pan aside for now.
Make The Cheesecake Filling : Beat the cream cheese in a mixing bowl with an electric hand mixer until creamy and smooth.
8 ounces full-fat cream cheese
Add the powdered sugar and vanilla extract. Beat on low speed, scraping down the sides of the bowl as needed, until thoroughly combined.
1/2 cup powdered sugar, 1 teaspoon vanilla extract
Using a wooden mixing spoon or a silicone spatula, stir in the egg until the cheesecake mixture is smooth and shiny. * You want to mix in the egg by hand to avoid over-mixing the egg into the cheesecake batter. 1 large egg
Pour the cheesecake batter evenly over the chocolate cookie layer in the pan. Smooth the top carefully with a spatula to ensure even coverage.
Using the remaining cookie dough, crumble and flatten small pieces of it in your hand and drop gently over top the cheesecake layer. * It might not be a perfect layer, and that's ok, just do your best to evenly cover the cheesecake. Bake for 35 minutes or until the cookie dough is cooked and the edges are golden brown.
Allow the bars to cool completely, at room temperature for about an hour, before cutting into squares. Store the cheesecake bars in the fridge and eat chilled.