Add the finely ground almond flour to a bowl along with the stevia, vanilla and melted butter.
Stir everything together well and press the mixture into the bottom of a 8-inch or 9-inch spring form pan (if using an 8-inch pan, the mixture will go up the sides a little bit).
Bake for 10 minutes and then remove it from the oven to let it cool.
For the cheesecake filling:
Turn your oven down from 350 degrees to 325 degrees.
Mix the cream cheese and baking stevia together with a hand mixer or stand mixer (fitted with the paddle attachment) until creamy and smooth. Be sure your cream cheese is at room temperature.
Add the sour cream and mix well to combine.
Add the eggs and egg yolks one at a time, just until incorporated. Don't over-mix when adding the eggs as this can create air bubbles in the batter which will cause the cheesecake to crack.
Mix in the vanilla, lemon juice and zest, and salt, just until combined. Scrape down the sides of the bowl to make sure everything is incorporated.
Pour the cheesecake filling into the prepared (and cooled) crust and tap it on the counter gently so any air bubbles rise to the surface.
Bake at 325 degrees for 1 hour and 20 minutes if using an 8-inch pan (bake for one hour and 5 minutes if using a 9-inch pan). After baking for the recommended time the cheesecake should be set around the edges with a slight jiggle in the centre.
For the topping:
Right after removing the cheesecake from the oven, mix together the lemon juice, sour cream, and baking stevia in a bowl with a whisk until very smooth.
Spread the sour cream mixture over the top of the cheesecake while it's hot using an offset spatula.
Let the cheesecake cool to room temperature in the pan and then place it in the fridge to chill for 6 hours or overnight.
Slice and serve after chilling with some fresh berries.
Notes
It's important to use a sweetener in this recipe that can be substituted for sugar with a 1:1 ratio. Some low-carb sweeteners are almost twice as sweet as sugar and require only half the amount of sweetener to be added to a recipe. We like baking stevia or Swerve Granular Sweetener.This recipe can be made in an 8-inch round spring form pan OR in a 9-inch round spring form pan. If using an 8-inch pan, bake for 1 hr 20 mins. If using a 9-inch pan, bake for 1 hr 5 mins.