Taken from a note written in wiki downtime.
Levain:
70g active starter
120g plain flour
120g water
Leave for 3-4 hrs (at 21°C) to activate
Tangzhong:
45g bread flour
120ml whole milk
120ml water
Cook in a pan until a thick custardy mixture is obtained (the spoon can leave tracks where the bottom of the pan is seen)
(TWO LOAVES)
Dough:
Ideally, start dough at night (21:00 onwards), bulk ferment overnight, knock back about midday the next day and second ferment, then the next morning move to tins and ferment, to bake at night. Overall 2-3 day lead time.
Mix dry ingredients
Add milk & water
Gently press in liquid until firm; autolyse 30 mins
Add egg, tangzhong, levain
Mix to dough
S&F in bowl 5 min
Add butter MAKE SURE SOFT
S&F in bowl until bits between fingers stretch into window panes
Bulk ferm (about 6 hours at 21°C)
Knock back (just fold a few times on a worktop) and cut into 2 balls of dough
Second ferm (about 14 hours at 21°C)
Cut each dough ball into two, roll out and fold into a log then place at ends of a buttered bread tin.
Cover (oiled clingfilm is ideal) and ferment until dough is just peeking over the top of the tins.
Brush with lots of milk, enough that the
Oven at 180°C non-convection bottom shelf ~35 mins
Cool 10 mins in tin, 1hr on rack