I struggled for the longest time to understand why AOC hasn't become a hard-to-get-a-table-on-weekends 5th Ave restaurant. Unfortunately, I think it's due to the owners' sense of dignity and a refreshing lack of gimmickry. Regardless, if you want classic French bistro cuisine expertly prepared and served by a mostly French staff (unconfirmed... they could be Quebecois?), we skip Moutarde, which lost its soul in the 2009 renovation, and go one block south to AOC.
I stick to the basics at a bistro, and all are wonderful here. Steak tartare is prepared table-side, to your liking, and is perfectly delicious, served with toasted baguettes. The portion is easily shareable by two. Every salad I've had there has been dressed to perfection. Moules frites have three preparations and all are glorious. I would put their AOC burger up against the best in the city. The ambiance is lovely, reserved and intimate, a perfect quiet date place. They keep the music soft so that people don't have to scream at each other. Highly recommended.