For the almond crust, in a small mixing bowl, combine powder sweetener, almond flour, salt, ground cinnamon, and melted unsalted butter. Mix until fully incorporated.
For the cheesecake, in a small mixing bowl, combine softened cream cheese, sour cream, softened unsalted butter, key lime zest, key lime juice, and powdered sweetener. Whisk until fully combined and smooth.
Place the almond crust at the bottom of a cup and top it with the cheesecake mixture. Refrigerate for at least 2 hours and enjoy with some whipped cream and key lime zest!