Whisk together the flour, baking powder, salt and rosemary in a large bowl.
Cream the butter and granulated sugar with an electric mixer until light and fluffy, 4 to 6 minutes. Add the egg, vanilla and orange zest and mix to combine. Add the flour mixture and mix until thoroughly combined. Cover with plastic wrap and refrigerate until firm, about 1 hour.
Preheat the oven to 350 degrees F. Line 2 baking sheets with parchment.
Roll the dough into 1-inch balls (about 1 tablespoon each) and place 1 inch apart on the prepared baking sheets. Bake until just golden at the edges, about 15 minutes.
Meanwhile, mix together the confectioners' sugar and reserved orange juice in a medium bowl and set aside.
Remove the cookies from the oven and let cool on the baking sheets about 5 minutes, then top each with about a teaspoon of the orange glaze.
This recipe was created by a contestant during a cooking competition. It has not been tested for home use.