Peel carrot, celeriac. Wash, peel and slice champignons.
Add carrots, celeriac, bay leaves and allspice to the pot. Add 2.5L of water.
Cook for 1h on high flame. Discard celeriac, bay leaves and allspice (if you can find them), keep carrots in the pot.
Boil water for cooking fussili and cook them according to instructions on the box (usually 10-12 minutes). Strain and put aside when ready.
Put olive oil in the pan. Add mushrooms. Sprinkle 1 tbsp of salt on top.
Fry for a couple of minutes until most of the released water evaporates. By then mushrooms should be soft and dark.
Add water to the pot to increase level back to 2.5L.
Add mushrooms to the pot (ideally move there as well as much of the residual olive oil as you will manage).
Add MSG, soy sauce and pasta to the pot.
Cook for 10 more minutes.
Add cream.
Add salt and pepper to adjust taste.