Mix instant coffee, hot water, and sugar to make coffee extract. Mix all together and set aside.

In another bowl, separate the egg yolk and white. Beat egg yolk and cup (50g) sugar until white (mixed for about 7-8 minutes).

Mix in 2T coffee extract. Place the remaining coffee extract aside

In another bowl, make meringue with egg whites and cup (50g) sugar.

Divide the meringue whites into two parts and mix with the egg yolk. Mix the meringue carefully with a spatula so that it won't breathe.

Mix together the sifted flour and salt. Do not mix too much. Mix together the flour and salt to keep you breathless.

Pour sponge cake batter into baking pan with baking paper. (I used a 28cm x 43cm baking pan).

Spread sponge cake flat in baking pan with dough scraper.
Lay flat and bake at 375F (190C) for 8-10 minutes.

While baking the cake, spread a clean cloth and sprinkle with powder sugar.

After baking the cake, place it on the cloth. Remove the baking paper from the cake and roll the cake round with cotton cloth.

Cool it until the end (~1 hour).

Cream the cake while it is cooling. Mix together the whipped cream and sugar.

When the cream has hardened to a certain extent, add the remaining coffee extract and mix.

Mix cream until meringue.

Dissolve rolled cake at room temperature. Beat slowly so that the cake doesn't stick to the cloth.

I'd like some mocha cream. Don't put too much cream on the end of the roll cake. When you roll the roll cake, the cream pops out.

Roll out the mocha cream and roll the roll cake without cotton cloth. Place cake in refrigerator for 1 hour after baking.

Store it in the refrigerator and sprinkle powder sugar on top and enjoy it!