Preheat oven to 350°F. Line a 9×5-inch loaf pan with parchment paper.
In a mixing bowl, beat the softened butter and sweetener until fluffy.
Add the ricotta cheese and beat until smooth.
Mix in the eggs, one at a time.
Add lemon zest, lemon juice, and vanilla extract.
In a separate bowl, combine almond flour, baking powder, and salt.
Add dry ingredients to the wet ingredients and stir until combined.
Pour batter into the loaf pan and smooth the top.
Bake 45–55 minutes or until a toothpick comes out clean.
Let cool completely before slicing. Dust lightly with powdered sweetener if desired.