Sweet Potato Yeast Rolls - cooking recipe

Ingredients

1 (1/4 ounce) package active dry yeast
1 cup nonfat milk, warm (110 to 115 degrees)
1 teaspoon granulated sugar
1/3 cup sweet potato, cooked, cold, mashed
2 eggs, separated
2 tablespoons unsalted butter, room temperature
1/2 teaspoon salt
1/3 cup granulated sugar (again!)
4 cups all-purpose flour
4 teaspoons cold water
1 tablespoon sesame seeds

Preparation

In a large mixing bowl, dissolve yeast in warm milk, then add 1 teaspoon of sugar & let stand for 5 minutes.
Add the sweet potatoes, egg yolks, butter, salt, the 1/3 cup sugar & only 2 cups of the flour.
Beat util smooth, then stir in enough of the remaining flour to form a soft dough ~ All of the last 2 cups of flour might not be used!
Turn onto a floured surface & knead until smooth & elastic, about 6-8 minutes.
Place dough in a bowl coated with cooking spray, turning once to coat the top.
Cover & let rise in a warm place until doubled, about 1 1/2 hours.
Punch the dough down, then turn onto a lightly floured surface & divide into 30 balls.
Roll each ball into a 10\" rope, then tie each rope into a loose knot.
Place the knots of dough 2\" apart on baking sheets coated with cooking spray.
Cover & let rise until doubled, about 30 minutes.
About 15 minutes before the rising is finished, preheat oven to 350 degrees F.
In a small bowl, beat egg whites & cold water. Brush this egg wash over the rolls, then sprinkle each with sesame seeds.
Bake for 15-17 minutes or until lightly browned.
Remove from pans to cool on wire racks.