I’m making a batch of donuts using more than 5lbs of flour. Do I need to take Hafrashat Challah?

I'm going to be making a large batch of donuts  with more than 5 lbs of flour. Do I do Hafrashat   Challah? Is that done with a bracha? How does that  work? Donuts are a special category because it's a   dough that's not baked. It's fried. It's boiled in  oil. When you make a dough to be boiled, according   to most poskim, it is not obligated in Hafrashat  Challah. However, there is an opinion that says   that it is obligated in Hafrashat Challah. So,  the Shach brings that in order to accommodate all   opinions, one should take Hafrashat Challah from  dough that's made for boiling. However, one does   not make a bracha. If one wants to be able to make  a bracha, there's a simple suggestion that's made,   that the Shulchan Aruch suggests, which is one  could take some of the dough and bake it. If   one takes off even a small piece of dough and  bakes that dough for eating, then that makes   the entire dough obligated now in challah and  then one could take off challah with a bracha.   But if one just is going to boil the entire batch,  then one takes off challah without a bracha.