Preheat the oven to 350°F.
Line an 8-by-8-inch baking pan with parchment paper, leaving overhang on two sides.
Lightly grease the exposed sides.
Combine the almond flour, powdered sweetener, and salt in a bowl.
Add the melted butter and vanilla.
Stir until the mixture resembles moist crumbs.
Transfer the mixture to the prepared pan.
Press firmly into an even layer using the bottom of a measuring cup.
Bake for 12 to 15 minutes, until lightly golden around the edges.
Remove from the oven and cool for approximately 10 minutes.
Reduce the oven temperature to 325°F.
Add the eggs and granulated sweetener to a large bowl.
Whisk until smooth.
Add the lemon juice, lemon zest, heavy cream, vanilla, and salt.
Whisk until combined.
Sprinkle the coconut flour over the mixture.
Whisk until smooth.
Let the filling sit for approximately two minutes.
Whisk again.
Pour the filling through a fine-mesh strainer for an extra-smooth texture.
Pour the lemon mixture gently over the crust.
Bake for approximately 20 to 25 minutes.
Remove when the edges are set and the center still has a slight wobble.
Cool at room temperature for approximately one hour.
Refrigerate for at least four hours or overnight.
Lift the chilled bars from the pan using the parchment paper.
Cut into 16 squares using a warm, clean knife.
Dust lightly with powdered keto-friendly sweetener before serving, if desired.
