Bennett became the club's youngest ever scorer at 16 years and 174 days, beating the previous record set by Lee Holmes in 2003, when he smashed in the fifth three minutes from the end.
"That was the highlight of the day for me," Clough said. "He could have scored one when he made his debut at Middlesbrough and hit the bar so it was lovely for him to get one today."
He added: "It's good because I think the experienced lads on the bench all understand that although all of them could have come on, it's vital for the younger ones to come on and get experience.
"One of the challenges we had was to bring some of the younger players through for the first team primarily and if they make us a profit at some point, all well and good, but I think this is the best place for them at the moment.
"To be fair, I didn't think it was a 5-0. We took our chances and got goals we don't normally score when the ball is bobbing around in the six yard box which was pleasing. The first goal was important because it settled everybody down and we went in at half time with a big boost."
League One leaders Rovers, 15 places below the Rams, initially started well but once Ben Davies capitalised on goalkeeper Owain Fon Williams' mistake in the 42nd minute there was no way back. Tranmere boss Ronnie Moore pinpointed the goalkeeper's error as the moment when the tie started to run away from his players.
"The turning point for me was the first goal," he said. "I thought we probably edged the first half so to concede was disappointing for us. We were flat at half time but to be fair, the keeper has been fantastic for us this season.
"He's made some unbelievable saves and he feels deep down he should have saved it but I'm not going to criticise him. He'll come back and hopefully keep a clean sheet next week. The basic defending just after half time was poor and really, we gifted them three goals but I think we can take a lot of positives out of the first half.
"I didn't think 5-0 was a reflection on how the game was. The last time we got beat 5-0 we won three league games on the trot ."