England set a huge target of 215 against the Kiwis after being asked to bat first and successfully defended it by restricting the hosts to 174 for nine in the allotted 20 overs, to begin their tour on a winning note.
Broad told Sky Sports 1 that this was their best win under his captaincy.
“Certainly [the best win] that I’ve captained,” he said.
“Looking back to the 2010 World Cup where we won we were fantastic throughout that tournament, but to go and get a record score of 214, that’s the exciting thing in the team, to have that mindset to go and get such a high score.
“A lot of the time you think 170, 180 is a good score. To go and get such a high score and defend it comprehensively, we’re delighted with that,” he said.
Broad, who claimed four wickets in the game, taking his overall wicket tally in the shortest format of the sport to 52 in 44 appearances – most for England – was not aware of the record.
“I didn’t know that. The freedom the guys played with the bat set us up brilliantly today. To lose the toss and then go and set our record score as an England batting line-up is fantastic,” he said.
“I think we learned a lot from batting on it first, knowing what we could bang out a heavy length, back of a length, and take the pace off to get the guys hitting to the bigger boundaries. It was probably not a bad toss to lose,” Broad added.
However, the English captain sounded warning for his side for the upcoming games to be played in Hamilton and Wellington.
He said, “It’s important we don’t get too carried away. We’ve two very important games coming up and Hamilton is a small ground again from what I remember, so we’ll have to be right on the money again.”