Grate pumpkin. Chop onion finely and roast them in oil. Add pumpkin and douse with a dash of vinegar. Pour beef stock on pumpkin, add some tarragon and simmer covered about 30 minutes. Spice wels fillets with salt, pepper and cover them both sides with flour. Rub out a pan with garlic, heat oil and butter and fry fish fillets both sides until brown. Refine pumpkin cabbage with cream and let them simmer 5 minutes more. Season to taste with salt and pepper.