1. Melt the butter in water, and stir in the milk.
2. The yolk protein is separated.
3. Then add egg yolk, sift in low-gluten flour, and mix well.
4. Add white sugar to the egg whites and beat until the whisk lifts up to an inverted triangle.
5. Stir the whipped egg white and egg yolk butter liquid from top to bottom.
6. Brush the mold with butter.
7. Pour the well-stirred into the mold.
8. Preheat the oven to 190 degrees, middle level, 10 minutes.
