1. Brush the inside of the mold with a small amount of liquid butter outside the formula
2. Add the whole egg mixture with fine sugar, beat the egg in the egg bowl over warm water
3. Until the egg liquid swells and turns white, lift the whisk, the dripping egg liquid can draw a figure of 8 and it will not disappear immediately
4. Beat at low speed for about 2 minutes, the custard becomes delicate
5. The milk and butter melt in water
6. Pour in the sieved low flour at a time, quickly and lightly toss the batter until no dry powder is visible (be careful not to over-mix to avoid defoaming and gluten in the batter)
7. Pour the melted milk and butter along the spatula into the batter, continue to stir evenly
8. Pour the batter into the mold and gently shake out bubbles
9. The oven is 160 degrees, the middle and lower floors, and the upper and lower fire is about 25 minutes (the temperature and time should be adjusted according to the actual oven of your own)
10. After being out of the oven, let it cool down on the drying net and release the mold (because the butter is brushed, the cake will leave the mold after a few minutes, please remove the mold in time to avoid the surface of the cake becoming wet due to moisture)
11. Wash the yam and steam it in a pot (just use chopsticks to pierce it through)
12. Peel and cut into small pieces, add appropriate amount of milk and sugar, and puree with a food processor (you can also directly use the back of a spoon to puree)
13. The yam mud is dug into a ball and placed in a cake cup, or refrigerated and piled into a soft ice shape, topped with blueberry jam or strawberry jam, chocolate sauce, and a little fruit to decorate
