In a bowl, combine the thinly sliced apples, lemon juice, granulated sugar, ground cinnamon, and a pinch of salt. Toss until the apples are evenly coated.

Place the apple mixture in a medium to large pot over medium-high heat. Slowly bring it to a boil, stirring occasionally.

In a separate bowl, create a slurry by mixing cornstarch with cold water. Set it aside.

As the apples release liquid and begin to soften, add the slurry to the mixture while stirring constantly. The mixture should thicken within about 30 seconds. If needed, prepare a bit more slurry to reach the desired thickness.

Once thickened, remove the apple mixture from heat and transfer it to a container. Let it cool to room temperature. The filling can be stored in an airtight container in the fridge for up to 1 week.

In a medium heavy-bottomed saucepan, combine the sugar, water, and corn syrup. Stir gently to moisten the sugar, then stop stirring completely.

Set over medium heat and cook undisturbed for 5–10 minutes, until the syrup turns a rich amber color. It can happen fast, so keep an eye out on it. Meanwhile, warm the heavy cream in the microwave for 1 minute.

Once the caramel is amber (like honey or copper), remove from heat. Carefully pour in the warm cream while whisking — it will bubble up quickly.

Whisk until smooth, then stir in the vanilla and salt. If needed, return to low heat briefly to smooth everything out.

Let cool slightly, then transfer to a heat-safe jar. The caramel will thicken as it cools. Refrigerate for up to a week and warm before using.

In a medium-sized bowl, combine the light brown sugar, all-purpose flour, ground cinnamon, and salt. Using your fingers or a pastry cutter, cut in the cold cubed butter until the mixture resembles coarse crumbs. This takes some time, so be patient. The mixture is done when there are no more flour streaks.

When the streusel is ready, place it in the fridge while you make the cheesecake batter.

Preheat the oven to 350°F (177°C). Line an 8x8-inch baking pan with parchment paper, leaving a little overhang for easy removal.

In a medium bowl, using a hand electric mixer, cream together the softened butter and brown sugar until smooth and creamy.

With a rubber spatula, scrape down the sides and bottom of the bowl. Mix in the egg yolk, vanilla extract, and salt until fully combined.

With the rubber spatula, gently fold in the flour and mix just until a soft dough forms. Do not overmix.

Press the dough evenly into the prepared pan, smoothing the top with your fingertips or the back of a spoon.

Bake for 12–15 minutes, or until lightly golden around the edges.

Set aside to cool slightly while you prepare the cheesecake layer.

Lower your oven to 325°F (163°C). Using any kind of baking dish, I used an 9x9 square but you can use whatever you want, fill with hot water and place it on the bottom rack in the oven while you make the batter.

In a large bowl or stand mixer fitted with the paddle attachment, beat cream cheese on medium speed until smooth and creamy.
Gradually add sugar on low speed until fully incorporated. Scrape down the sides of the bowl.

Add the egg yolk and eggs, mixing just until combined. Scrape down the bowl again.

Gently fold in sour cream, vanilla, and cornstarch with a rubber spatula until smooth, avoiding overmixing to reduce air bubbles.

Pour the cheesecake batter into the pre-baked shortbread crust. Spread evenly.

Add the cooked apple filling on top, and then add all the streusel on top until it no longer covers the apple.

Place the cheesecake on the second rack of the oven, if your oven doesn’t have a second rack you can place it next to the dish with the hot water in it.

Bake for 50-55 minutes or until the edges are set and the center is slightly jiggly. If the middle is still jiggly, but the crumble is done, lightly cover with tin foil until the middle is slightly jiggly. Let it cool to room temperature on a wire rack. Once cool, refrigerate for at least 4 hours or overnight.

When the cheesecake is set up drizzle the caramel on top and serve cold!