In a large mixing bowl, beat 1 cup of softened unsalted butter with 1/2 cup of powdered sugar using an electric mixer on medium speed for about 3 minutes until the mixture is light and fluffy.

To the creamed mixture, incorporate 1 tablespoon of lemon zest, 2 tablespoons of fresh lemon juice, and 1 teaspoon of vanilla extract. Mix on low speed until all ingredients are just combined.

In a medium bowl, whisk together 2 cups of all-purpose flour, 1/4 cup of cornstarch, and 1/4 teaspoon of salt until evenly blended.

Gradually add the dry ingredients into the butter mixture, stirring gently until a soft dough forms. Be careful not to overmix.

Divide the soft dough in half and shape each portion into logs about 2 inches in diameter. Wrap the logs tightly in plastic wrap and chill in the refrigerator for at least 1 hour until firm.

While the dough chills, preheat your oven to 350°F (175°C). Line baking sheets with parchment paper.

Once chilled, unwrap the dough and slice it into 1/4-inch rounds. Place the slices evenly spaced on the prepared baking sheets.

Bake your Lemon Meltaway Cookies for 10-12 minutes, or until the edges are just golden while the centers remain pale.

After removing the cookies from the oven, let them cool on the baking sheets for about 5 minutes.

While the cookies are still warm, carefully toss them in a bowl with powdered sugar to coat them thoroughly. Then transfer them to a wire rack to cool completely.

Once your cookies have cooled completely, you can give them a second toss in powdered sugar if desired.