Garak and Quark's conversation about root beer in The Way of the Warrior:
G: "It's vile."
Q: "I know. It's so bubbly and cloying and happy."
G: "Just like the Federation."
Q: "But you know what's really frightening? If you drink enough of it, you start to like it."
G: "It's insidious."
Q: "Just like the Federation."
And of course, who could forget Garak's interpretation of The Boy Who Cried Wolf? "You should never tell the same lie twice."