Heat the butter or oil in a heavy casserole and saute the veal pieces lightly for a few minutes. Add the onions and continue to saute, stirring, until they are translucent. Pourin the wine and when it comes to a boil, add the chervil, a little salt nd pepper, and quarter cup of broth. Simmer, covered, very gently for about 50 minutes, or until the veal is tender. Check, and if more liquid is needed during the cooking, add a little more broth. When done, stir in the cream. Meanwhile, cook the fiddleheads in 1 litre of boiling salted water for 5 minutes, or until almost tender. Drain, mix gently into the veal, and simmer about 3-4 minutes more. Taste and correct the seasoning, if necessary. Recipe By : L.L. Bean Book of New England Cookery