In a bowl, mix together the butter and the cornstarch until they’re well combined. Add in the powdered sugar, lemon zest and extract until it’s smooth. Add in flour and mix until the dough comes together and the flour is all incorporated. Cover and refrigerate 10-15 minutes.
Preheat 350 degrees F. Line cookie sheets with parchment paper & set aside.
Scoop out the dough into about ½ tablespoons of dough. I use this small cookie scoop. Roll the dough into a ball and lay them on parchment on a cookie sheet in rows (4 across by 5 rows) fitting about 20 per baking sheet.
Bake for 9 minutes and remove them from the oven. While still hot and fresh, flatten the tops of the cookies by gently pressing them down with the bottom of a glass. Let them sit for minutes before transferring the parchment to a cooling rack.
Let the cookies continue to cool for about 10 minutes before topping with glaze. Spoon the glaze over the tops of the cookies.
Let the cookies cool and set before storing in an airtight container.
How to make the cookie glaze
Melt 3 tablespoons of butter and stir in 1 teaspoon of lemon juice + 1 tsp lemon zest with 3 tablespoons of milk. Whisk in 1 cup to 1.5 cups of powdered sugar. Stir until it’s smooth and the desired consistency is reached. Let the glaze cool slightly before spooning on to the cookies. Top with additional lemon zest, if desired.
Notes
**Please Note: If you live in a more humid climate, or close to sea level you will need to add more flour to this recipe. So instead of using just 1 cup of flour in the recipe, you’ll need to use 1.5 cups and bake at least 3 or 4 cookies as a small test batch to make sure that the cookies don’t spread too thin.