Turn the dough back out of the bowl onto the floured surface and deflate it gently.
Using a scale, divide the dough into 12 pieces, 78 grams each. Don't flour them as you cut them.
Make balls out of each by rolling each piece of dough on an un-floured section of the counter under a cupped hand until you feel it come together in a tight, sphere-ish shape.
Place them on a parchment-lined sheet tray.
Cover the dough balls with another sheet of parchment, and squash them down with another sheet tray until they are somewhat flattened.
Make the egg wash by vigorously beating the two whole eggs and the single yolk. An immersion blender works well.
Baste the buns with the egg wash. Put them in an area where they can proof at around 75–80°F (24–27°C). Use a ChefAlarm's high- and low-temp alarms to make sure your proofing box—whether it be a cooler with some warm water, an oven with the light on, or a cardboard box set in a sort-of sunny place—doesn't get too hot or too cold.
Proof for about 90 minutes or until doubled in volume. (If you live in a very dry climate or your proof box is very dry, you may want to very lightly drape some plastic wrap over the buns to prevent them from drying out.)