In a small bowl, dissolve the sugar in the warm water.
Sprinkle the yeast over the surface; do not stir; let stand for 15 minutes.
In the bowl of an electric mixer, with a dough hook attachment, or in a large mixing bowl, mix together the flour, salt cinnamon and sugar.
Add the prepared yeast along with the melted butter, 1 egg, 1 egg white, and vanilla extract.
Knead with the mixer's dough hook for about 5 minutes or mix together, with a wooden spoon, until the dough comes together; then knead by hand for about 10 minutes.
You may need to add a little more flour as you knead, if your dough is too sticky; this is not unusual when making yeast doughs of any kind.
Whether you are using an electric mixer of making the dough by hand, you should always knead the raisins into the dough by hand; the mixer tends to crush the raisins and you want to keep them intact, so gentle hand kneading is best to incorporate the raisins into the dough.
Cover and let stand, in a draft-free, warm place for 30 – 40 minutes.
Grease a 9 x 13-inch baking pan.
Divide the dough into 12 equal pieces and form into balls.
Place them in the prepared pan and let rise for about an hour or until about doubled in size.
Pre-heat oven to 350°F.
In a small bowl or cup, whisk together the reserved egg yolk and 1 1/2 tbsp. water.
Brush over the tops of the buns before baking.
This step makes a glossy finish to the tops of the buns.
Bake for about 30 to 35 minutes or a little longer.
Remove from pan and let rest on a wire rack for about 15 to 20 minutes before piping on the vanilla glaze crosses.