Preheat your oven to 350°F (175°C).
In a medium bowl, combine almond flour, cocoa powder, erythritol, baking powder, and salt.
In another bowl, whisk together the eggs, apple sauce, vanilla extract, and Greek yogurt until smooth.
Gradually add the dry mixture to the wet ingredients, stirring until just combined.
Pour the batter into a greased 9-inch round cake pan.
Bake for 25-30 minutes or until a toothpick inserted in the center comes out clean.
Allow the cake to cool in the pan for 10 minutes before transferring it to a wire rack.
Once cooled, frost with your favorite low-carb frosting or serve plain.