1. Separate the egg whites and egg yolks, and put the egg whites in a container without water and oil.
2. Put the pure coffee powder into the container, pour 30ml of boiling water, and dissolve the coffee completely.
3. Pour in the cocoa powder and stir thoroughly.
4. Pour in egg yolks and 20 grams of fine sugar, and stir until the sugar is melted.
5. Pour in whipped cream and mix well. (If there is no light cream, add 45ml milk and 50g salad oil)
6. Sift in low-gluten flour and stir evenly in a "Z" shape.
7. Add 3 drops of white vinegar to the egg white, add the remaining 50 grams of caster sugar in three times, and beat until hard foaming. Lift the egg beater meringue to have a small sharp corner.
8. Take half of the meringue and add it to the chocolate batter and mix well. (At this time, the oven can be preheated, 130°, upper and lower fire)
9. Pour the stirred batter back into the remaining egg whites and mix well.
10. Pour the mixed batter into an 8-inch hollow mold and gently shake it twice to produce large bubbles.
11. Put it in the preheated oven, 130°, upper and lower fire, lower layer, bake for about 60 minutes. After being out of the oven, shake it a few times, buckle, and demould after it is completely cooled.
