In mixing bowl of stand mixer combine yeast, water and sugar let sit 5 mins.
In seperate bowl mix flour, salt, poppy seeds and onion flakes. Add to yeast mix and mix with dough hook for 6-8 mins. until dough forms an elastic dough ball. Put into an oiled bowl and set aside with a cloth over it for 30 mins. or until doubled in size.
Spinkle flour on counter and turn out the dough, make 12 balls roll them and place on a greased baking sheet, let rise 30 mins.
Boil 6 cups of water and add 1/3 cup baking soda when it is at a roiling boil. Put rolls in 3 or 4 at a time for 30 sec. on each side, put back on baking sheet and sprinkle with salt (if using) Bake at 350 degrees for 15-20 mins. or until golden brown and feels done in the middle.