The head coach has seen his stock rise immensely over the past three years.
During an interview with The Standard, Frank admitted he had turned down other job offers.
He stated: “Yeah, I have. But I doubt I'll find a club that does everything better than Brentford. I've got a good daily life, which is important.
“What will happen in the future, I don't know. I'm very ambitious — that could be here, that could be somewhere else.
“If it turns out that I one day move, it's because I felt that was the right decision. But there's too much I want to improve here."