Heat
Nimono
The figure
Dashi 8 : soy 1 : mirin 1
Drop-lid, low heat. Hard things first, seasoning late.
The rule
Broth just to cover. An otoshibuta holds the steam so the surface does not dry. Bring to a boil on medium, skim, then low.
Hard first: roots, then konnyaku and atsuage, then meat. Seasoning late. Dark soy at the start salts only the outside.
When it is done
Potato: until a skewer runs through. Carrot in rounds: 12 to 15 minutes. Beef in nikujaga: the last 5 minutes. Overcooking tightens the fibre.