Preheat oven to 350 degrees F. Line a rimmed baking sheet with a silicone baking mat or parchment paper.

Beat butter at medium speed with a stand mixer until creamy. Add 1/2 cup powdered sugar and beat at medium speed until light and fluffy. Stir in zest and juice. Whisk together flour and next 2 ingredients. Gradually add flour mixture to butter mixture, beating at low speed just until blended. Cover and chill 1 hour.

Using a 1-inch cookie scoop, drop dough by spoonfuls 2 inches apart onto parchment paper-lined baking sheets.

Bake, in batches, at 350F for 13 minutes or until lightly browned around edges. Cool on baking sheets 5 minutes.

Toss together warm cookies and remaining 1 cup powdered sugar in small bowl. Transfer to wire racks, and cool completely (about 15 minutes).