Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.
In a large mixing bowl, combine the softened cream cheese and unsalted butter. Using an electric mixer, beat until smooth and creamy.
Add the powdered erythritol and the medium egg to the creamed mixture. Mix until well incorporated and fluffy.
Gradually add the almond flour, lemon juice, and lemon zest into the wet mixture. Mix on low speed until dough forms and just combined. Do not over-mix.
Using a cookie scoop, portion out the dough onto the prepared baking sheet, leaving space between cookies.
Bake for 12-15 minutes, or until edges are lightly golden. Watch carefully to avoid over-baking.
Remove from oven and let cookies cool on the baking sheet for about 5 minutes before transferring to a cooling rack.
In a small bowl, whisk together powdered erythritol, lemon juice, and additional lemon zest until smooth for the glaze. Adjust sweetness to taste.
Once cookies are completely cooled, drizzle glaze over each cookie and allow to set for a few minutes.