Like so much of New Orleans culture, Pascal’s Manale, which dates back a century or so, is puzzling and irresistible. Its signature dish, and one now found on many Louisiana-inspired menus, is barbecued shrimp: huge, head-on crustaceans served in a pool of garlicky, peppery butter. Why they’re called “barbecued” is anybody’s guess, but my-oh-my, are they ever good! Toasty and succulent, fresh and firm, they are a royal mess to eat (those who order them are trussed in a paper bib by the waiter), requiring much picking and poking. Once you get the hang of it, you’ll be removing the plump pink crescents from their shells in no time, alternately mopping at the juice with the frail French bread provided