Preheat your oven to 350°F (175°C). In a food processor, crush Biscoff cookies until fine. Melt unsalted butter and mix it with the crushed cookies until it resembles wet sand. Press this mixture firmly into the base and up the sides of a lined 9-inch springform pan. Chill the crust in the refrigerator while you prepare the other components.

In a mixing bowl, combine melted butter, all-purpose flour, brown sugar, and rolled oats. Stir until crumbly and evenly combined, with no large clumps remaining. Set this aside to cool slightly.

In a medium pot, combine your sliced tart apples, brown sugar, cornstarch, and a sprinkle of cinnamon. Cook over medium-high heat for about 5-7 minutes, stirring occasionally, until the apples soften and a syrup begins to form. Once thickened, remove the apples from heat and let them cool.

Lower the oven temperature to 325°F (160°C). In a large mixing bowl, beat together softened cream cheese, granulated sugar, Greek yogurt, vanilla extract, and spices until smooth and creamy, which should take about 2-3 minutes. Add the eggs one at a time, mixing each until fully incorporated.

Retrieve your chilled crust from the refrigerator and pour the cheesecake filling over it. Carefully spoon the cooked apple mixture over the top, followed by the crumble topping, distributing it evenly.

Place your assembled cheesecake on a sheet pan to catch any drips and bake in the preheated oven for 65-70 minutes. The edges should be set while the center remains slightly jiggly.

Once baked, remove the cheesecake from the oven and let it cool completely. Cover it loosely and refrigerate for at least 6 hours, or preferably overnight.