Mix all the ingredients except butter and knead into a smooth dough. Add small pieces of butter and knead until it expands. In warm places, the basic fermentation is twice as large.
Mix all coconut materials evenly. I rub them with my hands.
Ventilate and knead the fermented dough, and relax for 15 minutes.
Roll the dough into a rectangle about 40cm long, sprinkle with coconut milk evenly, leaving 1cm on the side, and then roll it up gently.
Put some oil on the knife, divide the long dough into 10 equal parts, and put it into an 8-inch round mold. Ferment in a warm place to double the volume.
Brush the surface with egg liquid, put it in a preheated 170 degree oven for about 25 minutes, and cover it with tin foil after the color is satisfactory.