Separate the egg white yolk and beat the egg yolk in a bowl. Add sugar a, starch syrup, and salt, whip to medium, then add water little by little and whip until sugar and salt are dissolved. Just to the point where it'

Put the whites in a bowl and whip about 60% of the foam, then add sugar b and whip the meringue until the tip of the meringue is bent (the shape of an eagle's toenail) to make the meringue. Add 1/3 meringue to egg yolk whipped bowl and lightly mix with spatula.

Add the pre-sieve flour and baking powder, mix lightly with #, place cooking oil in a bowl, add a little dough, and mix again into the main dough.

Add the remaining meringue and mix quickly, keeping the meringue from turning off. Mix part of the dough with caramel pigment or chocolate syrup and prepare it in a piping bag or vinyl (this process may be omitted) Place parchment paper in a pan, pan the dough, and make the dough even with a scraper.

I don't have caramel coloring, so I used chocolate syrup. Put it in a piping bag and make a pattern. Bake in preheated oven at 170 degrees for 15-20 minutes.

Remove the cooled cake from the parchment paper, spread the wet cotton cloth or parchment paper on the floor, turn the cake upside down, and spread the mulberry jam. After making cuts on the edges, place the rolling pin on the bottom and roll. Leave it for a while and cut it