The building shown as Castle Lecter in Lithuania is in fact in Belgium. Chateau de Noisy, originally named Chateau Miranda, was completed in 1866 and demolished in 2017.
Following the pattern used in the previous seasons (to use as episode title terms relatives to a dish or a dish preparation - French cuisine in the first season and Japanese cuisine in the second) the third season use Italian nomenclature. Secondo (literal translation "second" - meant as in second plate not second as measure of time) is a main dish in Italian menu that follow the Antipasto (starter) and "Primo" ("First Plate" - i.e. pasta or risotto).
Punch Romaine was the last drink served to the first-class passengers on the Titanic- perhaps a nod to the fact that Hannibal knows the end is coming, but that he intends to keep playing as the ship sinks.