Mix together all the dry ingredients except for the salt. Add 200 ml water (reserve the rest for adjustment) and egg yolks.
Blend together and knead until the dough forms a ball. Add butter and salt, knead until the dough does not stick to the bowl anymore and becomes elastic.
Roll the dough long, cut into 20-30 g pieces, roll each dough into a ball. Cover with plastic, let them rise twice their initial volume (about 1-2 hour).
Brush the surface with a runny mixture of egg and milk, bake at 180 degree celsius until done.
Cut the bun in half, let it stale overnight. The next morning, turn on your oven at160-170 degree celsius, spread it with Butter Spread, bake until crisp.
Butter Spread: Mix all ingredients together until fluffy.
