1. Preparing the Graham Cracker Crust

1. Preheat the Oven: Preheat your oven to 325°F (163°C).
2. Prepare the Pan: Spray a 9×9-inch baking pan with non-stick spray. Line the bottom and two sides with parchment paper, leaving an overhang on the sides for easy removal. Spray the parchment paper lightly with baking spray.
3. Crush the Graham Crackers: Use a food processor to crush the graham crackers into fine crumbs.
4. Mix the Crust Ingredients: In a bowl, combine the graham cracker crumbs, brown sugar, and melted butter. Stir until the mixture resembles wet sand.
5. Press the Crust into the Pan: Pour the crumb mixture into the prepared pan. Use your fingers and the bottom of a measuring cup to press the crumbs firmly into an even layer.
6. Pre-Bake the Crust: Bake for 10 minutes. Let it cool while preparing the cheesecake layer.

Note: Pre-baking the crust helps it set, ensuring a firm base that won’t become soggy once the cheesecake layer is added.

2. Making the Cheesecake Layer

1. Beat the Cream Cheese: In a large bowl, beat the room temperature cream cheese on high speed for 1 minute until smooth.
2. Add the Sugar: Gradually add the sugar and beat for another minute until fluffy. Scrape down the sides of the bowl to ensure even mixing.
3. Incorporate the Creams and Vanilla: Add the sour cream, heavy cream, and vanilla extract. Beat on medium speed until the mixture is smooth and lump-free. Scrape the bowl as needed.
4. Add the Eggs: Add the eggs one at a time, mixing on low speed until just combined after each addition. Avoid overmixing to prevent cracks during baking.
5. Final Check: Ensure the batter is smooth and free of lumps before pouring it over the cooled graham cracker crust.

Note: Scraping the bowl between steps ensures that all ingredients are fully incorporated, preventing any lumps or uneven textures in the final cheesecake.

3. Creating the Chocolate Chip Cookie Dough

1. Sift the Dry Ingredients: In a bowl, sift together the flour and salt.
2. Cream the Butter and Sugars: In a separate bowl, beat the butter, white sugar, and brown sugar together on high speed for 2 minutes until light and fluffy.
3. Add the Vanilla and Egg: Mix in the vanilla extract and egg until well combined. Scrape down the sides of the bowl.
4. Incorporate the Dry Ingredients: Slowly add the flour mixture to the wet ingredients, mixing on low speed until just combined.
5. Add the Chocolate Chips: Fold in the chocolate chips until evenly distributed throughout the dough.

Note: For variations, consider adding nuts like chopped walnuts or substituting the chocolate chips with dark or white chocolate for a different flavor profile.

4. Assembling the Bars

1. Layer the Cheesecake Batter: Pour the prepared cheesecake batter over the cooled graham cracker crust. Spread it evenly with a spatula.
2. Add the Cookie Dough: Flatten small amounts of cookie dough into discs and place them on top of the cheesecake layer, covering most of the surface.
3. Evenly Distribute the Dough: Spread the dough evenly across the entire surface, leaving some cheesecake visible for a marbled effect.
4. Final Check: Ensure the layers are even before baking.

Note: A well-distributed cookie dough layer ensures that each bar has a balanced amount of cheesecake and cookie dough in every bite.

5. Baking and Cooling

1. Bake the Bars: Bake in the preheated oven for 50-60 minutes, or until the edges are set and the center has a slight jiggle.
2. Check for Doneness: Look for golden brown edges and a center that is slightly set but still jiggles when gently shaken.
3. Cool the Bars: Remove from the oven and cool completely at room temperature.
4. Refrigerate for Final Setting: Once cooled, cover the pan and refrigerate for at least 6 hours or overnight.

Note: Allowing the bars to cool slowly and refrigerating them ensures the cheesecake layer sets properly and the bars are easy to cut.

6. Serving and Storing

1. Cutting the Bars: Use the parchment paper to lift the bars out of the pan. Cut into squares with a sharp knife, wiping the blade between cuts for clean edges.
2. Serving Suggestions: Serve the bars as is, or drizzle with chocolate or caramel sauce. Pair with coffee or a glass of milk for the perfect treat.
3. Storing the Bars: Store in an airtight container in the refrigerator for up to 5 days. For longer storage, freeze the bars individually wrapped in plastic.