Does anyone have a good recipe for Ryba Po Grecku? (Fish Greek style).

Does anyone have a good recipe for Ryba Po Grecku? (Fish Greek style). A traditional dish at Wigilia.

Fish in Greek sauce (Ryba w sosie greckim)

1kg cod (fried)

Sauce ingredients:
50mL(or less) oil
2.5 glass (~625 mL) of water
½ kg carrots
200g celery root
150g onion
150g parsley root
tomato paste
salt, pepper, sugar to taste

Preparation:
Boil the water and oil in a pot. Add chopped onion and grated carrots, celery and parsley roots. Cook on low heat until soft. Add tomato paste, salt, pepper and sugar to taste

I never heard of this before today - when my sister-in-law called to tell me she was bringing some for Wigilia!!! I hope it is good!!

IT'S the BEST!!! ;))