Preheat the oven to 325°F (163°C). Line a 9x9-inch (23x23 cm) baking dish with parchment paper, leaving an overhang on two sides for easy removal.
In a medium bowl, combine the graham cracker crumbs and granulated sugar. Stir in the melted butter until the mixture resembles wet sand. Press the mixture firmly and evenly into the bottom of the prepared pan. Bake for 8 minutes, then remove from the oven and set aside to cool slightly.
1½ cups (150g) graham cracker crumbs, ¼ cup (50 g) granulated sugar, 6 tbsps (85 g) butter
In a large mixing bowl, beat the softened cream cheese and granulated sugar until smooth and creamy. Add the eggs one at a time, mixing on low speed just until combined after each addition. Mix in the Greek yogurt (or sour cream), vanilla extract, and flour until smooth. Fold in 1 cup of the chopped Butterfinger candy bars.
16 oz (454 g) full-fat cream cheese, ½ cup (100 g) granulated sugar, 2 large eggs, ½ cup (120 g) full-fat plain Greek yogurt, 1 tsp (5 ml) vanilla extract, 2 tbsps (16 g) all-purpose flour, 1 cup (150 g) chopped Butterfinger candy bars
Pour the cheesecake batter evenly over the pre-baked crust and smooth the top. Bake for 35 to 40 minutes, or until the edges are set and the center is slightly jiggly. Remove from the oven and allow to cool completely at room temperature.
Once cooled, spread the caramel sauce evenly over the cheesecake layer. Sprinkle the remaining chopped Butterfinger candy bars over the caramel and gently press them in to adhere. If desired, drizzle with melted semi-sweet chocolate (easy to do in the microwave on a low setting).
½ cup (160 g) caramel sauce, 1 cup (150 g) chopped Butterfinger candy bars, ½ cup (85 g) semi-sweet chocolate chips
Refrigerate for at least 4 hours, or overnight, until fully set. Use the parchment overhang to lift the bars from the pan. Slice into 16 squares, wiping the knife clean between cuts for neat edges.