Confused, please assist with the sizes here in

Joanna Chang runs nine large bakeries plus a restaurant so I'm guessing she'll not have the time to answer this. I took a look at the recipe. Looks like if you make the entire dough recipe, you'll have enough for 8 rolls. So you have the choice of having 4 extra rolls or using half of the dough for something else.

So with that half amount of dough, divide that into four equal parts. There is a technique involved in shaping the dough into the approx 4" sized balls. It's not hard to do but it's hard to "describe in writing". You know what a I mean? You kind of stretch the dough and tuck it under and repeat. Look for a breadmaking video on youtube that shows what the stretch & pull under motion entails. The end result will be like a little baby's bottom.

The cake pan is probably your standard 8" or 9" square pan (I gleaned that from the picture where the egg is cut in squares). You bake the eggs in the square pan and put the pan in a water bath, like you would cheesecake.

Hope that helps a bit. I'd love to visit Flour Bakery one day. Joanne Chang has a such an interesting biography and an amazing instagram page where she shows the staff cooking. You may enjoy it. If you do make this, report back. I'm really curious.