Preheat the oven to 160°C or 320F.
Prepare the apple by peeling and dicing it. Heat a pan on medium heat, add butter, diced apples, brown sugar alternative, lemon juice, cinnamon, and nutmeg. Cook for 5-8 minutes.
Mix water and cornstarch, then add to the cooked apples. Cook for another 1-2 minutes until thickened. Set aside to cool down.
Mix wet cheesecake ingredients using a whisk or electric hand mixer until just combined and no clumps remain. Sift in the dry ingredients and whisk until well combined.
In a separate bowl, mix the flour, melted light butter, sweetener, and cinnamon until a crumble forms.
In a lined pan, pour the cheesecake batter, top with the cooked apples, then sprinkle the crumble on top.
Bake at 160°C for 35-40 minutes over a bain-marie, then increase the temperature to 180°C for an additional 5-10 minutes.
Allow it to cool, then refrigerate overnight, or minimum 5 hours.
Cut into 12 slices and enjoy.