In a large bowl, dissolve the yeast in warm water. Add 1 teaspoon sugar and let stand for 5 minutes.
In an 8 oz liquid measuring cup, combine the warm milk, ¼ cup sugar and salt.
Add the lukewarm milk mixture, butter, egg, cinnamon, cloves and 1 cup flour to the dissolved yeast mixture. Beat until combine.
Stir in the raisins and dried currants.
Gradually stir in the 2 ¾ cups of flour, adding more flour if needed, to make a soft dough which leaves the sides of the bowl. Turn onto a lightly floured surface.
Knead, adding more flour as needed, until a soft dough is achieved, about 5 minutes.
Place the dough in a greased bowl, turning once to grease the top. Cover with a kitchen towel and let rise in a warm place until doubled, 60 to 90 minutes.
Punch down the dough. Turn onto a lightly floured surface. Divide into 15 equal pieces. Shape each piece into a smooth ball. Place 2-inches apart on a parchment lined baking sheet. Flatten the balls slightly. Cover with kitchen towels and let rise in a warm place until double, 45 to 60 minutes.
Preheat the oven to 375 degree F.
Using a sharp knife, cut a cross on top of each bun.
In a small bowl, whisk together the egg yolk and 1 tablespoon water. Brush top of the buns with the yolk mixture.
Bake in the center of the oven for 15 to 20 minutes or until golden brown. Remove from the pans to wire rack to cool for 10 minutes.
If using icing, in a small bowl, mix together the confectioner’s sugar and milk. Fill a pastry bag or a Ziploc bag with the icing mixture, snip the tip (or cut a tiny hole in the corner) and then pipe a cross on top of each bun.