Alex Hales hit 94 from 61 balls as he combined in a 111-run stand with Michael Lumb (43) - a record opening partnership for England against Australia - as the hosts reached 195 for five.
Jade Dernbach then took three for 23 as Australia fell short, despite 53 from David Warner.
Broad pointed to the all-round nature of the performance: "After losing the toss the guys adapted to the conditions really well. To get 60 off the first six without losing a wicket was fantastic...and it was great to keep wickets in hand."
He also hailed Dernbach, saying: "You can't ask for much more than the last two games, he's been fantastic."
Of the series, Broad added: "Both batting performances have been exceptional. We have had two fantastic wickets to play on, there's not much margin for error.
"It shows in international cricket you need to have your skills perfect. It's been a long summer, it's been very special and will always hold some good memories."
Opposite number George Bailey said: "I thought we had some good patches with the ball. It was really tough with the wind.
"There are some really good things going on. Finchy's innings (Aaron Finch scored 156 in first match) was fantastic and I like the balance with the batting order."
For Hales, his 94 was bitter-sweet given he fell just six short of his century, the second time in his short career he has just failed to become the first England batsman to score an international Twenty20 ton.
The 24-year-old opener was agonisingly a single run short of a century against West Indies at Trent Bridge last year and was denied his moment when he holed out in the deep in the penultimate over from James Faulkner.
Hales said after the match: "I'm disappointed not to get there having got to 94. It was a fantastic team effort and set the tone early with the bat on what was a fantastic wicket.
"Lumby helped me out, he was brilliant at the start. We formed a good partnership."
Of his international ambitions, Hales added: "I've got a lot of hard work to do and a lot of runs to score for Notts."
- Sports & Recreation
- Alex Hales
- Jade Dernbach
- Michael Lumb