Preheat the oven to 350°F. Lightly grease a 9 x 5-inch loaf pan.
Using a vegetable peeler or sharp paring knife, remove the zest from the orange. taking care to remove just the orange part not the white pit which has a bitter taste.
Combine the orange zest and sugar in a food processor and pulse until zest is finley ground.
Transfer the sugar mixture to a large bowl and add the butter. Beat with an electric mixer on medium speed until light in color, about 3 minutes, scraping down the sides of the bowl as necessary. Beat in the eggs, one at a time and beating well after each addition. Beat for another 2 minutes.
Reduce the mixer speed to low and beat in the baking powder, salt, and the the flour, alternately with the buttermilk, beating just until blended.
Using a rubber spatula, fold in the cranberries. Scrape the batter into the prepared pan and smooth the top.
Bake until fully risen and a toothpick inserted near the center comes out without wet batter clinging to it, about 50 minutes. Let the bread cool in the pan for 10 minutes, then remove from the pan and let cool completely.
Make the glaze: In a small bowl, combine the powdered sugar with enough orange juice to make a thick glaze. The glaze should be thick and barely pourable. Spread the glaze over the cooled bread. Top with orange zest and sugared cranberries.