1. Preheat oven to 350°F. Grease a 9-by-5-inch loaf pan and dust with flour, knocking out excess. Sift together flour, baking powder, baking soda, cinnamon, salt and cloves onto a sheet of waxed paper.
2. Using an electric mixer on medium-high speed, beat yolks and sugar until pale. Mix in honey and butter until smooth. Reduce speed to low; add half of flour mixture, then milk, then remaining flour mixture. Fold in candied ginger.
3. In a clean, dry bowl, beat egg whites until they form soft peaks. Fold 1/3 of whites into batter, then fold in remaining whites. Transfer batter to loaf pan and bake until a skewer inserted in center comes out clean, about 1 hour. Let cool on a wire rack for 10 minutes, then turn out of pan and let cool completely. Sift confectioners' sugar over top just before serving, if desired.