For the dough, mix all ingredients (except butter) together, and then knead it for 3 minutes at low speed. Then the below rough dough would be formed.
Add butter then knead it at medium speed for 4 minutes, until a smooth dough is formed.
Knead the dough into round shape, then let it rise under a warm condition until its size is doubled. Cover it with wet cloth otherwise the dough will be dried out.
[Time may vary under different weather condition, in Summer it can be an hour, in Winter it can be 2 hours.]
Wait for the dough to reach its double size to move to the next step
Divide the dough by 12 portion (57g @), knead them into round shape and let them rest for 15 minutes.
Knead each round dough into round shape again, then let it proof for 30 minutes at least, the size should be doubled.
[The last proofing time depends on weather also. In Summer it can be 30 minutes, in Winter it can be 1 hour. ]
For top ingredients, first take butter out of the fridge to let it soften. Then mix it well with icing sugar. Flour is then added in to mix everything well together.
Divide the batter by half. Melt the coffee powder and matcha powder with hot water separately before adding to the batter.
Roll the batter into large plain rectangle then freeze it for an hour at least
Cut round shape out from the plain batter, ~100mm ring can be used. Then place them on top of the bread dough.
Pre-heat the oven for 3 minutes at 240℃, then bake for 17 minutes, at 180℃.
[Fan option of the oven would be good to be picked. Every oven are different, have to do some testing to see which duration and temperature suit the best.]
