Step 1

Preheat the oven to 350 degrees F. Line a cookie sheet with parchment paper.

Step 2

In a large bowl, beat together the butter and 1 cup powdered sugar with an electric mixer on medium speed. Stir in flour, cornstarch, lemon zest, and vanilla and mix well.

Step 3

Form the dough into 3/4-inch balls and place them on the prepared cookie sheet about 1 1/2 inches apart. Flatten them a little with your palm.

Step 4

Bake in the preheated oven for 9 to 11 minutes, or until edges are lightly browned. Allow the cookies to rest for 2 minutes and then transfer to a wire rack to cool completely.

Step 5

For the icing, whisk together 1 cup powdered sugar, lemon juice, and zest in a separate bowl. If the mixture is too thick, add more lemon juice. If it's too thin, add powdered sugar to thicken.

Step 6

Once cookies have cooled, dip the tops in icing and place back on the parchment paper. Give the icing 15 to 30 minutes to set. The cookies will need to set for at least 24 hours.

Step 7

The icing to fully dry. But if you're not too worried about the icing being a little wet, feel free to enjoy right away!