For the cheesecake filling combine the softened cream cheese, egg, sour cream, confectioners monkfruit, lemon juice, lemon zest, and vanilla extract in a mixing bowl. Beat the mixture with an electric mixer until smooth.

Spoon the mixture over the crust.

To make the crumble topping add cold butter, almond flour, pecans, sweetener, and lemon zest to a bowl or food processor. If using a food processor pulse until the mixture resembles a course crumb topping. If using a bowl use a pastry cutter to cut the butter into the flour mixture until a crumble topping forms.

Sprinkle the crumb topping on the cheesecake bars.

Bake the cheesecake 25-30 minutes until the cheesecake has set in the center. If the crumble topping begins to brown too quickly place foil loosely over the top of the cheesecake.

Allow the bars to come to room temperature before placing in the refrigerator. Chill the bars at least 2 hours before slicing.