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

In a large mixing bowl, cream together the softened unsalted butter and powdered sugar until light and fluffy, about 3-5 minutes.

Add in the cornstarch, all-purpose flour, fresh lemon zest, fresh lemon juice, vanilla extract, and a pinch of salt to the creamed mixture. Mix on low speed until combined.

Scoop out the cookie dough and roll it into 1-inch balls. Place on the prepared baking sheet and flatten slightly.

Bake for 10-12 minutes until edges are lightly golden and centers appear soft.

Allow cookies to cool on the baking sheet for 5 minutes, then transfer to a wire rack. Dust with powdered sugar while warm.