WASHINGTON—During an unexpected visit Thursday to an organizational meeting for this year's White House Christmas party, Vice President Joe Biden winked mischievously as he offered to "handle" the eggnog supply for the upcoming annual event. "Uncle Joe's got the nog under control," said Biden, briefly flashing a metal flask protruding from the inside pocket of his suit jacket. "Old family recipe." Biden's appearance among White House event planners was his first since last May, when he offered to procure "some real fireworks" for the upcoming Fourth of July festivities.