I am a HUGE fan of this restaurant. Visits to Montreal absolutely suck unless they include a meal here.
I am addicted to the Mouse de foie de voillaie appetizer. Pure sex in a ramekin. It's a mix of various fowl livers topped with pistachio's served with fresh french bread. Delicious is an inadequate adjective.
I am also addicted to their steak tar-tare. It is difficult at best to find this classic in the States and nearly impossible to find it done well. At L'Express it is exceptional. I take mine extra spicy. Served with impeccable frites it is a joy for my palette.
On our recent visit we enjoyed Il Flotante for dessert. A light fluffy meringue floating in caramel sauce. This was the only sub-par item we had. The caramel chunks in the sauce were simply too large and unmanageable. On previous visits these were broken into small pieces. This was a small oversight but one the chef should address.
Service here is always impeccable albeit very formal and a bit stuffy. In part this is because this is definitely a "see and be seen" establishment. We dined next to a local news anchor although I must admit I didn't know who he was or what all the fuss was about.
All told this is a fantastic restaurant. If you're going to Montreal do not miss the opportunity to have classic French Bistro food done well. You will not be disappointed.