Place sliced almonds in food processor and process with cutting blade until a finely ground.
Pulse in low carb sugar substitute and cinnamon (if using).
Stir in melted butter.
Press into bottom of 9-inch springform pan. Set aside. NOTE: I used a 9-inch pan, but a 10-inch pan can be used as well for a shorter cheesecake. You can also pre-bake the crust for 8-10 minutes to make it crisper.
Beat cream cheese on low speed until light and fluffy.
Add low carb sugar substitute. Beat on low to mix in.
Add each egg, one at a time, beating on low after each addition.
Mix in extracts, then beat in sour cream on low speed until incorporated.
Spread cream cheese mixture over crust.
Bake at 325°F for about an hour and fifteen minutes (I find it's better to lower the temperature to 300°F when using a dark pan) just until the top has browned and center is still jiggly. Keep an eye on it at the end of baking time as ovens can vary. Turn oven off.
Leave cheesecake in oven with door ajar for an hour. Then, remove from oven and cool completely on a wire rack before transferring to the refrigerator.
Chill at least 24 hours before serving.
Crushed low carb cookies are perfect for using in the crust or crumbling into the filling. Just sub crushed cookies in place of the almonds, sweetener, and cinnamon!I find ¾ cup sweetener is just right. But those just getting started on keto may want to increase the amount up to 1 and ½ cupsTips to prevent the cheesecake from cracking:
Make sure all the ingredients are room temperature.
Don’t over mix! Over-mixing can cause the top to crack.
Bake for an hour. Then turn oven off and let it cool in the oven for at least an hour then remove and allow to finish cooling at room temperature. A slow cool helps prevent cracking.
Use a pan of water in the oven to make it steamy while preheating and keep it in the oven during baking.