Start by mixing the graham cracker crumbs with melted butter until evenly coated. Press the mixture firmly into the bottom of a springform pan, making sure it’s compact. Bake briefly so the crust sets and doesn’t become soggy later.
Beat the softened cream cheese with sugar until smooth and fluffy. Add sour cream, vanilla, and eggs one at a time, mixing gently to avoid overbeating. Pour the filling over the cooled crust and smooth the top.
In a saucepan, combine sliced apples, brown sugar, cinnamon, nutmeg, and flour. Cook until the apples soften and the mixture thickens slightly. Let it cool for a few minutes before layering it over the cheesecake batter.
Mix flour, brown sugar, oats, and cinnamon in a bowl. Cut in the cold butter until the mixture forms coarse crumbs. This topping adds texture and that classic apple crisp finish.
Spoon the apple mixture evenly over the cheesecake filling, then sprinkle the crisp topping on top. Bake until the center is set but still slightly jiggly. Turn off the oven and let the cheesecake cool gradually.
Once cooled to room temperature, refrigerate the cheesecake for at least four hours. This chilling time helps the flavors develop and ensures clean slices when serving.