David Meyler's header and Robbie Brady's 25-yard free-kick meant Troy Deeney's late reply was a mere consolation but Bruce thought his team's created enough to merit more reward.
Bruce said: "Watford in the second half were better but the first half I can't really remember my goalkeeper having a touch of the ball and we've had two chances in the first three minutes which we've missed.
"But we knew Gianfranco's (Zola) team would be different in the second half,
they're on a great run of form but I think we were worthy winners. We could have been and should have been out of sight."
On his upwardly mobile side, now fourth, Bruce added: "We've tried to play, we've tried to entertain, I'm delighted that the supporters are enjoying what they're seeing.
"I've got some good players who have adapted very quickly in three or months to a different regime, a different manager, a different formation, a different style if you like but I think they're enjoying it.
"Certainly I've enjoyed working with them because they're a very, very good group and let's hope we can keep continuing."