X is a refined slip of a place, noteworthy since it’s helmed by Danny Brown, whose namesake restaurant in Forest Hills was a Michelin-starred destination for several years before it closed. He named X for a bistro he used to love in Paris, the brief menu recalling what he savored there. The choices, which include a plate of smoked salmon, a slab of pâté and preparations of foie gras, duck breast and beef, are all impeccable. The wine list, of course, focuses on French varietals. Upper East Siders are lucky he relocated, but be advised there are just five tables and 10 seats at the copper-topped bar.