It’s “And now for something completely different” three times a year as Grant Achatz shape-shifts the identity of his stunning culinary adventure. Executive chef Dave Beran’s 14th menu, Tapas, grew out of his and Achatz’s tour of the finest tapas and pintxos bars in Barcelona and San Sebastian. Offerings may be as intricate as octopus with charred eggplant and fennel in liquid foam or as simple as translucent slices of jamón Ibérico de Bellota. Servers bubble with enthusiasm. The current menu, inspired by the French Laundry, runs through December 31. For tickets, visit Next’s website (nextrestaurant.com).