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

In a large mixing bowl, cream unsalted butter and powdered sugar together until light and fluffy, about 2-3 minutes.

Add cornstarch, all-purpose flour, lemon zest, fresh lemon juice, vanilla extract, and a pinch of salt. Mix on low speed until just combined into a soft dough.

Roll small portions of dough into 1-inch balls and place them on the prepared baking sheet, spacing 2 inches apart. Flatten each slightly.

Bake for 10-12 minutes until edges are lightly golden and centers remain pale.

Allow cookies to cool on the baking sheet for 5 minutes, then transfer to a wire rack to cool completely.

Once cooled, dust generously with powdered sugar before serving.