Melt butter in the microwave. Preheat oven to 350°F. Place 1 inch of water in a tray on the bottom oven rack to create steam. Line a 7-inch springform pan with parchment paper.

In a bowl, mix almond flour, cinnamon, and stevia. Add melted butter and stir until crumbly.

Press mixture into the bottom of the pan. Bake for 10 minutes. Remove from oven and reduce temperature to 300°F.

In a large bowl, beat cream cheese until smooth. Add powdered sweetener, stevia, lime juice, and heavy cream. Mix well. Add lime zest.

Add eggs one at a time, mixing gently after each. Stir in sour cream just until combined.

Pour batter over the crust and smooth the top. Bake on the middle rack for 60 minutes.

Remove from oven and cool at room temperature for 1–2 hours. Refrigerate overnight.

Garnish with lime slices before serving if desired.