Spoilers for all of A Series of Unfortunate Events Season 3 follow. A secret organization is bound to have a few, well, secrets. And the biggest mystery surrounding the V.F.D. in A Series of Unfortunate Events has been: what's in the Sugar Bowl? Even readers of Daniel Handler's books didn't know for sure what this dishware contained, which has led to plenty of theories about the Sugar Bowl over the years. But the Netflix series answered this mystery in the series finale, "The End," so fans can now know for sure if their theories were right.
The answer to what's in the Sugar Bowl in A Series of Unfortunate Events is rather obvious since the Sugar Bowl really does contain (what else?) sugar. But before you feel too let down by this simple explanation, Kit Snicket further reveals to the Baudelaires that the sugar contains a vaccine to the deadly medusoid mycelium. The sugar comes "from a botanical hybrid V.F.D. developed to defend us from the mycelium," Kit says. "Horseradish cures you, the hybrid immunizes you."
The Baudelaires attempt to get their hands on the Sugar Bowl throughout Season 3, but they fail. They also learn that Esme Squalor's obsession with a matching tea set led to the V.F.D. schism since Beatrice and Lemony stole the bowl so that the hybrid could be used to save others. Although the Baudelaires were unsuccessful in obtaining the Sugar Bowl , they thankfully are able to save themselves from medusoid mycelium since their parents had "recreated the botanical hybrid in the tuberous canopy" on the island. So, like in the books, these horseradish-apple hybrids save them.
In multiple interviews, including one with the Observer, Handler had said that there was an answer to what was in the Sugar Bowl. And he finally revealed the answer through the A Series of Unfortunate Events Netflix show. But now that the story of the Baudelaire orphans is over and the truth is out there, see how some theories about what could've been in the Sugar Bowl hold up.