2. Add 50 grams of sugar, yogurt and corn oil to the egg yolk and mix well.

3. Sieve in low powder

4. Stir evenly again until it is bright yellow and has no graininess.

5. Add a total of 1 10g sugar into the egg white for two or three times until the egg white is dry and bubbly, as shown in the figure.

6. Add one third of the protein paste into the protein paste and stir it evenly, then stir it up and down with the rest of the protein paste.

7. Bake in the middle and lower layers of the oven 160 degrees for 45 minutes, and put a baking tray on the upper layer to prevent the color from being too dark.

8. Take it out of the oven and hang it for a while.