Crack the egg into a bowl. Add the sugar, corn oil, warm milk, and high-sugar-tolerant yeast.

Using chopsticks, stir thoroughly until the sugar and yeast are completely dissolved and the mixture is smooth with no visible granules.

Gradually pour the liquid mixture into the bowl of flour while stirring with chopsticks, forming a shaggy dough with no dry flour remaining.

Begin kneading by hand in the bowl, then transfer the dough to a work surface.

Knead using a press–fold–push motion for 10–15 minutes until the dough becomes smooth, fine, and no longer sticky.

The finished dough should reach the classic “clean bowl, clean hands, smooth dough” stage.

Roll the dough into a long log.

Divide the dough evenly into 6 portions, each weighing about 80 g.

Pick up one piece, holding it with one hand while using the other to roll and knead it continuously.

Cup your hand over the dough and move it in small, quick circular motions on the countertop, applying gentle downward pressure.

Continue until each portion forms a smooth, round bun with no cracks on the surface.

Using a knife, cut three shallow slashes on the surface of each bun (do not cut all the way through).

Turn the cut side facing down, then gently roll the bun under your palm to reshape it into a neat round. Repeat with all dough pieces.

Arrange the shaped mantou on a steamer lined with cloth, leaving space between each one.

Cover with plastic wrap or a damp cloth and let proof in a warm place (28–30°C / 82–86°F) until about 1.5 times larger.

Well-proofed mantou should feel light when lifted, spring back quickly when pressed, and look plump and airy.

Heat a non-stick pan or electric griddle over low heat with no oil.

Place the proofed mantou into the pan and lightly toast until the bottoms and sides just begin to colour, about 3 minutes. Remove and set aside.

Add enough cold water to the steamer. Place the mantou inside.

Once the water comes to a full boil and steam rises, begin timing and steam for 15 minutes.

Turn off the heat and do not open the lid immediately. Let the mantou rest inside for 3 minutes to prevent shrinkage.

Open the lid, remove the mantou, and serve while hot.

They should be tall, fluffy, softly cracked on top, and fragrant with a gentle milky aroma.