For American diners, this dish is highly unusual; for French diners, it is a rare delicacy. During spawning season, the male pike’s internal organs enlarge. Chef Lacombe dresses out a whole pike and reserves these delicacies, sauteing them to a golden brown in butter as a side dish. Fishmongers can save these parts for you — in season — and Chef Lacombe says they freeze well. The remainder of this dish, the poached pike dumplings, or quenelles, with classic Sauce Nantua, may be made without the side dish any time of year.