Preheat the Oven: Begin by preheating your oven to 325°F (163°C). While the oven is heating, line a 9x13-inch pan with parchment paper for easy removal of the bars after baking.
Prepare the Crust: In a mixing bowl, combine 1 ½ cups graham cracker crumbs, ¼ cup sugar, and ½ cup melted butter. Mix until the crumbs are well-coated. Press this mixture firmly into the bottom of the prepared pan, creating an even layer. Bake in the preheated oven for 10 minutes, then remove and let cool slightly.
Make the Filling: In a large mixing bowl, beat 4 packs (8 oz) cream cheese and 1 cup sugar with an electric mixer until smooth and creamy. Add 4 eggs one at a time, ensuring each egg is fully incorporated before adding the next. Then, mix in 1 cup sour cream, ¼ cup heavy cream, 2 tbsp lemon juice, 2 tbsp lime juice, zest from 1 lemon & 1 lime until everything is well blended and smooth.
Combine and Bake: Pour the cheesecake filling over the cooled crust in the pan. Ensure it is spread evenly. Place the pan in the oven and bake for 45-50 minutes. The cheesecake should appear set with a slight jiggle in the center. After baking, turn off the oven and crack the door open; let the cheesecake cool in the oven for 1 hour to prevent cracking.
Prepare the Cherry Swirl: In a small saucepan, heat 1 cup cherry preserves and 1 tbsp lemon juice over low heat, stirring until smooth. Once the cheesecake has cooled, gently swirl this cherry mixture over the top for a beautiful and delicious topping.
Chill: Cover the pan with plastic wrap or foil and refrigerate the bars for at least 4 hours or overnight for the best results. Before serving, sprinkle ¼ cup chopped pistachios on top for added texture and flavor.