1. Preheat oven to 350°. Line a baking sheet with parchment paper.
2. Beat butter and 1 cup powdered sugar at low speed with an electric mixer until smooth. Beat in lime zest. Add flour and ground almonds gradually, beating until well blended. Chill 15 minutes.
3. Shape dough into 1-inch balls; place 1 inch apart on prepared baking sheets. Bake 10 minutes or until light golden brown on bottom. Let stand on baking sheet 2 minutes.
4. Roll warm cookies in remaining 1 cup powdered sugar, coating well. Let cool completely.