Classic Coffee Roll Cake

I always long for this kind of recipe, classic, simple, and delicious. 

This roll cake is different from the recipe that I usually make, it's a sponge cake with a lot of egg yolks (almost the same weight). It has more body than a simple sponge, it is not as soft as the chiffon and you can create a pattern on top of the cake too. Most of all it's my mom's favorite.

The first time that I tested the recipe I used an adjustable cake frame to make a 25x35 cm. cake but luckily, I found the roll cake pan that was exactly the size that I wanted when I went to the Taiwan bakery show, and now I use it instead. Anyway, you can use a 30x30 cm. pan too.

The trickiest parts of this cake are the oven temperature and baking time, as the roll cake will crack easily if you bake it too long while the top (the pattern part) will stick to the baking paper (after rolling) if it is not dry enough. So, you may have to adjust the time and temperature to suit your oven.

I use a fine powder type of instant coffee, if yours is a large granule type please weigh it instead.

The coffee batter for making patterns

1 1/2 tbsp .....................  Instant coffee granules (6g)

1 1/2 tsp ........................ Water

1 ...................................  Egg yolk

Cake batter

40 g ............................. Unsalted butter

80 g ............................. Cake flour

1/8 tsp .......................... Salt

110 g ............................. Egg yolk

40 g ..............................  Granulated sugar (A)

1 tsp .............................  Instant coffee granules (1.5g)

120 g .............................  Egg white

40 g .............................  Granulated sugar (B)

Coffee mixture for buttercream

15 g .............................  Golden syrup

1 tsp .............................  Water

2 tsp .............................  Instant coffee granules (3g)

Italian meringue buttercream

1 tbsp ............................ Water

60 g  ............................. Granulated sugar (A)

50 g .............................  Egg white

12 g .............................  Granulated sugar (B)

150 g ............................. Unsalted butter (soft)

1/8 tsp .......................... Salt

*I use a fine powder type of instant coffee, if yours is a large granule type please weigh it instead.

Preheat the oven to 180℃.

Line a 25x35cm roll cake pan with baking paper.

*you can use a 30x30 cm. pan too.

Make the coffee batter for making patterns

Put all the ingredients into a small bowl, and mix until fully combined.

Put the batter into a piping bag and set it aside.

Melt the butter in the microwave and let it cool slightly.

Use it when it's about 40℃.

Sift the flour and salt together and set aside.

Beat the egg yolk and sugar until light in color.

Add the instant coffee granules and mix to combine. Set it aside while making the meringue.

Beat the egg white until foamy, add the sugar gradually.

Beat until firm peaks formed.

Put 1/4 of the meringue into the egg yolk bowl and mix slowly with a whisk.

Fold the rest of the meringue in 3 additions.

Fold 1 cup of the batter into a warm butter bowl and set it aside.

Fold the sifted flour in 3 additions.

Pour the melted butter mixture into the bowl.

Fold to combine.

Pour the batter into the prepared roll cake pan and level the top.

Pipe the pattern mixture over the cake batter.

Drawing lines with the tip of a skewer.

Tip: Drag the stick along the edge of the cake to keep the edge of the cake neat when baking.

 Tap the pan to remove large air bubbles.

Bake for 12 minutes in the the180℃ preheated oven.

Remove the cake from the pan and cover it with a new piece of baking paper.

Let the cake cool completely while making the buttercream.

Make the buttercream

Mix the Coffee mixture ingredients together in a small bowl and set aside.

Put the water and sugar (A) in a saucepan and place over medium heat.

Beat the egg white until foamy add the sugar (B) and whip until soft peaks formed.

Boil the syrup until it reaches 115℃.

Slowly pour the hot syrup into the meringue (beating all the time).

Continue beating until cool.

Add the butter gradually into the meringue bowl and beat to combine.

Put the coffee mixture and salt into the bowl and beat to combine.

Use a spatula to mix the butter (this will remove some air from the buttercream).

Trim the end of the cake obliquely.

Flip the cake, and trim the opposite end of the cake obliquely too.

Spread the buttercream over the cake.

Roll the cake into a cylinder.

Use the ruler to tighten the cake by pushing it while pulling the paper.

Tip: Put into Log Cake mold (if you have it) the shape of the cake will be more beautiful.

Refrigerate until set before cutting it into pieces.

Classic Coffee Roll Cake