Patterned Roll Cake | How to Make a Roll Cake Wrapped Without Breaking It? | Banana Roll Cake

Pattern Roll Cake
Materials
4 eggs
1 teaspoon of granulated sugar
Half a cup of hot water
1 teaspoon of flour
Half a teaspoon of starch
2 soup spoons of cocoa
1 packet of baking powder
1 packet of vanilla
In between: dr oetker pastry cream (you can also make pastry cream at home)
+banana