Preheat oven to 325 degrees.

Grease 8-inch springform pan and line with parchment paper.

Crust: Heat butter in a saucepan over high heat, stirring often. One butter foams remove from heat and allow to cool for 10 minutes. Slowly add the chocolate (chopped) to the butter over medium-high heat stirring constantly. One melted, add erythritol, and stevia. Let cool in fridge. Once cool, add egg, cinnamon, vanilla extract, and salt. Place mixture in the springform pan, spreading to cover bottom completely.

Filling: Beat cream cheese, erythritol, stevia, almond milk, vanilla extract, almond extract, and salt until well blended. Add eggs one at a time, mixing on low speed until just blended. Pour half the batter into the springform pan. 

Cinnamon Swirl: Heat butter over high heat, stirring often until it foams. Whisk in erythritol, stevia, vanilla extract, cinnamon, and salt. Remove from hear and let cool slightly. 

Spoon half of the cinnamon swirl on to the filling. Using a knife, cut the cinnamon swirl through the batter several times, making a marble effect. 

Top with remaining filling. 

Top with cinnamon swirl and cut in for marble effect. 

Water Bath: Wrap aluminum foil entirely around bottom and halfway up the sides of the springform pan. Place cheesecake in a roasting pan and place in the oven. Pour hot water into the pan so that it comes halfway up the sides of the springform pan.

Bake for 55 minutes or until center is almost set.

Remove from over and let cool completely in pan before removing it. 

Refrigerate for 4 hours before serving.