* The original recipe said to use only 2 tablespoons of butter and 1 yolk with 1 tablespoon of water. I felt the mixture was too grainy and wasn't coming together, so I kept adding the melted butter, then another yolk, and a little more water until it looked more like a dough. I read different versions of the recipe to decide what the dough should look like: some is crumbly, some is more sticky. I went for the kind of crumbly but sticky dough.
ANOTHER IMPORTANT NOTE (also detailed in my post): The original recipe said to make the stock with chicken thighs, then "reserve the thigh meat for another use." Why would I make CHICKEN stock for CHICKEN soup, then use the meat for ANOTHER USE? I considered making the stock from the thighs as directed, then using that meat for the soup. However, I also wanted to make this recipe a little easier with a little less hot stove work in the summer, so I opted to skip the thighs altogether, use the suggested breast meat for the soup, and used canned broth for the soup. Any broth will do, but I caution against "full sodium" canned broth as you may end up with a very salty soup. You could try one can of full sodium broth, then use water to make up the difference to 2 quarts of liquid. It's best to cook with less salt in the beginning, then add more after all soup components are in the pot.