Preheat oven to moderate baking temperature

Line a square baking pan with parchment paper

Combine almond flour, sweetener, and salt in a bowl

Stir melted butter into dry ingredients until crumbly dough forms

Press crust mixture evenly into prepared pan

Bake until lightly golden and set

In separate bowl, beat cream cheese until smooth

Add eggs, sweetener, lemon juice, zest, vanilla, and baking powder

Mix until completely creamy and lump-free

Pour lemon filling over pre-baked crust

Return pan to oven and bake until center is just set

Remove and allow bars to cool completely

Chill briefly for cleaner slicing

Cut into squares and serve