Scald the cornmeal
Mix the cornmeal with boiling water until it comes together into a doughy mixture. Let it cool until warm to the touch.

Mix the dough
Add the egg, flour, yeast, sugar, warm water and melted butter mixture. Knead until the dough is smooth and soft.

Shape and rise
Divide the dough into 10 equal pieces, roll each piece into a ball, and place on parchment paper or a greased steamer tray. Cover and let them rise in a warm place until noticeably puffy.

Steam
Bring water in the steamer to a boil. Steam over high heat for 12–15 minutes. After steaming, turn off the heat and let them rest for 2–3 minutes before opening the lid to prevent shrinking.