1. Prepare the Baking Pan

Start by preheating your oven to 350°F or 175°C. Line a rectangular baking pan with parchment paper, leaving some overhang on the sides. This makes it easier to lift the bars out once they have cooled. Lightly grease the parchment to prevent sticking.

This step is crucial because these bars have multiple layers and a soft texture. Without proper lining, removing them cleanly can become difficult.

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2. Make the Crust

In a large mixing bowl, combine the softened butter, brown sugar, and granulated sugar. Cream the mixture until it becomes light and fluffy. This process helps create a tender base.

Add the flour and salt gradually, mixing until a soft dough forms. The dough should be slightly crumbly but hold together when pressed.

Transfer the dough into the prepared pan and press it evenly across the bottom. Use your hands or the back of a measuring cup to create a smooth, compact layer.

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3. Pre-Bake the Crust

Place the crust in the oven and bake for about 15 minutes or until it is lightly golden. This pre-baking step ensures that the crust remains firm and does not become soggy when the cheesecake layer is added.

Remove from the oven and allow it to cool slightly while preparing the filling.

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4. Prepare the Cheesecake Filling

In another bowl, beat the softened cream cheese until smooth and free of lumps. Add the sugar and continue mixing until well incorporated.

Add the eggs one at a time, mixing gently after each addition. Stir in the vanilla extract. The mixture should be silky and creamy.

Avoid overmixing at this stage, as too much air can cause cracks during baking.

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5. Assemble the Cheesecake Layer

Pour the cheesecake filling over the slightly cooled crust. Spread it evenly using a spatula, making sure it reaches all corners.

This layer forms the creamy heart of the dessert, so taking time to spread it evenly ensures consistent texture in every bite.

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6. Prepare the Apple Layer

In a bowl, toss the diced apples with sugar and cinnamon until evenly coated. The sugar draws out moisture while the cinnamon adds warmth and depth.

Distribute the apple mixture evenly over the cheesecake layer. Try to spread them in a single layer to ensure even cooking.

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7. Make the Crumble Topping

In a separate bowl, combine oats, flour, brown sugar, baking powder, salt, and cinnamon. Mix well.

Add the cold butter pieces and use your fingers or a pastry cutter to work it into the dry ingredients until the mixture resembles coarse crumbs.

Sprinkle the crumble evenly over the apples, covering the entire surface.

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8. Bake the Bars

Place the assembled pan back into the oven and bake for about 35 to 40 minutes. The topping should turn golden brown and the cheesecake layer should be set.

You may notice a slight jiggle in the center, which is normal. It will firm up as it cools.

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9. Cool Completely

Remove the pan from the oven and allow it to cool at room temperature. Once cooled, transfer it to the refrigerator for at least 2 hours.

Chilling is essential because it helps the layers set properly, making the bars easier to slice.

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10. Add Caramel and Serve

Once chilled, lift the bars out using the parchment overhang. Drizzle the warmed caramel sauce generously over the top.

Slice into squares or rectangles and serve.

The caramel adds a glossy finish and enhances the flavor profile with a rich sweetness that ties all layers together.