Another NY option...
D'Artagnan Rotisserie on 46th b/w Lex & 3rd offers cassoulet too. Didn't have it when I was there (I had foie gras every course except dessert... "with a side of angioplasty, please...") but I enjoyed the restaurant very much. I'd have high hopes that their cassoulet would please.
In Montreal I'm afraid I'm not of much help on that score - I did enjoy Toque! very much, as well as St Viateur for bagels. And poutine... gosh, avoiding it would be like going to Philly and avoiding cheese steaks. Yes, it may seem gross to an outsider... but there's a reason it's the provincial dish.