1. Prepare the ingredients needed for the cake body.
2. Melt the butter in water and set aside.
3. Separate the egg white from the egg yolk with an egg separator, and add sugar to the egg yolk.
4. Stir the egg yolks well.
5. Insulated water is whipped until the color becomes lighter and emulsified, which is egg yolk paste.
6. Egg whites with sugar.
7. Dispense until almost dry foaming.
8. Take 1/3 of the egg whites into the egg yolk paste and mix well.
9. Pour back into the remaining egg whites and mix well.
10. Sift in low-gluten flour.
11. Stir the batter evenly.
12. Take 1/3 of the batter and add it to the previously melted butter.
13. Mix well.
14. Pour back into the batter and mix well.
15. Pour it into a baking dish lined with greased paper and shake out large bubbles.
16. Sprinkle black sesame seeds.
17. Preheat the oven at 160-170 degrees, middle level, up and down, 12-15 minutes.
18. Wait for the process to make the filling and prepare the materials.
19. The bananas are crushed into puree with a rolling pin.
20. The butter is softened at room temperature and powdered sugar is added.
21. Mix the butter and powdered sugar thoroughly.
22. Use an electric whisk to beat.
23. Add the fresh milk in portions and continue to beat.
24. Add the mashed banana.
25. Keep whipping smoothly.
26. After taking out the cake, let it dry for 5 minutes to remove the grease paper, and cut one end diagonally to remove the edges.
27. Spread the filling evenly, roll it up from one end to the oblique opening, and wrap it tightly with oiled paper.
28. Refrigerate in the refrigerator for 30 minutes to set, cut off both ends and then cut into sections for consumption.
Tips:The temperature is adjusted according to each oven.
