Former Brentford manager Frank replaced Postecoglou this summer after the Aussie was axed just weeks after leading Spurs to the Europa League title
Postecoglou made a shortlived comeback this season at Nottingham Forest, which meet Frank's Spurs today.
"I don’t know him personally, but I hope he comes back," said Frank. "He clearly loves being a coach and being in the game, so I always hope good coaches come back in.
"Ange has been in many ways a very successful Spurs manager. They had a very good first season here in the Premier League and they won their first trophy in don’t know how many years, and that’s definitely part of success.
"Also, he had that in the past at Celtic and so on. There’s a lot of circumstances about why things are good and why things are bad. I don’t think it’s my job to go into details about that.
"The only thing I can say is Ange is a legend and always will be. He won a massive trophy, he was a big part of that, and we all stand on the shoulders of us. I stand on the shoulders of Ange and now I’m trying to build on that."