Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.

In a medium bowl, whisk together the flour, cornstarch, baking powder, and salt. Set aside.

In a large mixing bowl, cream the softened butter and powdered sugar together until light and fluffy, about 3-4 minutes.

Add the lemon zest, lemon juice, vanilla extract, and almond extract (if using) to the butter mixture and mix until well combined.

Gradually add the dry ingredients to the wet ingredients, mixing until just combined. Do not overmix.

Using a cookie scoop or tablespoon, drop rounded balls of dough onto the prepared baking sheet, spacing them about 2 inches apart.

Bake for 10-12 minutes, or until the edges are set but the centers are still soft.

Allow the cookies to cool on the baking sheet for 5 minutes before transferring them to a wire rack to cool completely.

Once cooled, dust the cookies with additional powdered sugar for a sweet finish.