Prep the pan and oven. Heat oven to 325°F (163°C). Line an 8x8-inch square pan with parchment, leaving overhang for easy lifting.
Lightly grease the sides.
Mix the crust. In a bowl, stir almond flour, sweetener, and salt. Add melted butter and vanilla, and mix until it looks like damp sand and clumps when pressed.
Press and par-bake. Press the crust into the pan in an even layer. Dock with a fork a few times.
Bake for 8–10 minutes until set and lightly golden at the edges. Let it cool for 5 minutes.
Beat the cream cheese. In a mixing bowl, beat softened cream cheese on medium speed until smooth and fluffy, about 1–2 minutes. Scrape the bowl.
Add sweetener and flavorings. Beat in granulated sweetener, vanilla, and salt until smooth.
Mix in sour cream.
Add eggs. Beat in eggs one at a time on low speed just until blended. Do not overmix. If the batter is very thick, add 1–2 tablespoons heavy cream to loosen slightly.
Fold in chips. Gently fold in 1/2 cup sugar-free chocolate chips with a spatula.
Assemble. Pour the cheesecake batter over the warm crust.
Smooth the top and sprinkle the remaining 2 tablespoons of chips over the surface.
Bake. Bake at 325°F for 25–32 minutes, until the edges are set and the center wobbles slightly when you jiggle the pan. It should not be liquid.
Cool gradually. Turn off the oven, crack the door, and let the bars sit for 10 minutes. Move the pan to a rack and cool to room temperature.
Chill. Refrigerate for at least 3 hours, preferably overnight, until completely set.
Lift out with the parchment and cut into 16 squares with a hot knife, wiping between cuts.