For the Shortbread Crust:

1. Preheat your oven to 350°F (175°C).
2. Combine room-temperature butter, sugar, all-purpose flour, and a pinch of salt in a large bowl.
3. Mix until the ingredients resemble wet sand, ensuring the butter is evenly distributed.
4. Press the mixture firmly into a greased or parchment paper-lined 9×13-inch baking dish.
5. Bake the crust in the oven for 10 minutes or until it’s lightly golden.
6. Remove the crust from the oven and allow it to cool completely.
7. Toss the peeled and diced Granny Smith apples in a bowl with 3 teaspoons of Apple Pie Spice and 2 tablespoons of sugar until they are well coated.

For the Cheesecake Filling:

1. In a separate mixing bowl, beat the room-temperature cream cheese until it’s smooth and creamy.
2. Add the eggs and 1/2 cup of sugar, and continue to beat until the mixture is well combined and smooth.

For the Streusel Topping:

1. In another small bowl, combine 1 cup of sugar, 1/4 teaspoon of salt, all-purpose flour, chopped pecans (if using), and 2 teaspoons of Apple Pie Spice.
2. Pour the melted butter over the dry ingredients and stir until the mixture forms a crumbly texture.

Assembly and Baking:

1. Pour the cheesecake batter over the crust, spreading it out evenly.
2. Spread the diced apple mixture evenly over the cheesecake filling
3. Sprinkle the streusel topping evenly over the cheesecake layer.
4. Bake the assembled bars in the preheated oven at 350°F (175°C) for approximately 25-30 minutes or until the edges are golden brown and the center is set with a slight jiggle.
5. Remove the bars from the oven, allow them to cool in the pan for about 30 minutes, and finish in the fridge for at least 1 ½  hours.
6. Once cooled, remove from fridge, cut into squares, drizzle with caramel sauce, and serve.