The 19-year-old goalkeeper was thrust into the limelight when handed his professional debut midway through the first half of the Hornets' crunch final game of the regular season last term, with the Hertfordshire outfit gunning for automatic promotion from the Championship at home to Leeds.
But it was not the fairytale he had pictured as he shared the blame for Leeds' opener before dropping a clanger for the visitors' 90th-minute winner, forcing Watford into an ultimately unsuccessful play-off battle.
Bonham, released by the Hornets, became Brentford's first signing of the summer when he penned a two-year deal at Griffin Park earlier this week, and he is out to bounce back from his experiences last season.
"I spent six years there (at Watford), it was my first professional club; I also went through their schooling system that they have at the Academy," he told the Bees' official website.
"That's football, you have to move on and hopefully here I'll be able to progress my career.
"I'm here to make a point, I didn't end the season at Watford very well but I want to come back stronger. I've been working hard in the summer to get fitter, on things I can do better and hopefully push Simon (Moore) for the number one and when Richard (Lee) comes back from injury, try and keep the place from him."