“Would you like to let the wine mature, or shall I pour it right away?” Not what you’d expect to hear at a place where the star of the menu is a burger.

But this is the relaxed, no-reservations front cafe attached to Palena, Frank Ruta’s elegant dining room. In the cafe you get all the trappings of four-star dining—a proper fish knife arrives when you order a lemony cut of sturgeon—and casual doesn’t mean careless.

The rich spring-green aïoli next to Ruta’s terrific rabbit sausage is the best sausage-and-onions in town. A lovely poached guinea hen terrine comes with a mini chicory salad and no fewer than three kinds of pickled fruits and vegetables. And that burger? Its sesame bun, mayo, and pickles are all made in-house, and it’s sheathed with luxurious black-truffle-infused cheese.

While much of the ever-changing menu, be it a sharable plate of cod fritters or that dainty guinea hen terrine, hovers around $14 a dish, a cocktail and dessert will bump up the tab. Still, this is a chance to sample the cooking of one of the city’s most talented chefs without having to really splurge.

Open for dinner Tuesday through Saturday.