Dine one flight up, where the most desirable of a sea of tables overlooks the square below. Fittingly for a Belgian restaurant, mussels are the house specialty, in more than a dozen variations, from curried to Provençal, and in uniformly large portions. They are brought to the table in the cast-iron pot in which they were cooked. Double-fried potatoes are the delectable accompaniment, and complimentary second helpings are customary. A sturdy Muscadet goes well with mussels, and the wine list includes two good options. If mollusks aren't your thing, other options include veal cutlets and tournedos in 18 different sauces and preparations, and there's also a spicy steak tartare. Although the establishment is very popular, there's almost always an available table, even on a Saturday night.