Preheat oven to 350 degrees F (175 degrees C). Grease a donut pan.
Whisk the All-Purpose Flour (1 cup), Salt (1/4 teaspoon) and Baking Powder (1 teaspoon) into a bowl.
In another bowl, cream the Unsalted Butter (1/4 cup), Orange (2 teaspoon), and Granulated Sugar (1/2 cup) until light and fluffy. Add the Egg (1) and beat until incorporated. Mix in half of flour mixture.
Mix in Milk (1/4 cup) add remainder of flour and Orange Juice (1/4 cup) mixing well after each addition.
Fill donut pan about 2/3 full. Bake for 15 minutes until golden.
Combine Powdered Confectioners Sugar (1 cup) and Orange Juice (1 tablespoon) to make the icing. Let cool slightly before dipping into icing.