Ese'ese played NRL games for Canterbury, Brisbane, Newcastle, Gold Coast and the Dolphins before linking up with Hull for the 2024 season.
The 30-year-old powerhouse celebrated his new contract extension, running until 2029, in style during an impressive away win.
Ese'ese underscored his worth to Cartwright's revitalised Black and Whites as he shrugged off the attentions of three Castleford defenders to bustle over for the opening try with 10 minutes on the clock.
"It's massive for the club. Herman is scoring tries at will and he's good to have around the club - he's a great team man and a club man," Cartwright said of Ese'ese's new long-term deal.
"He never misses training, he plays big minutes and he is probably the best front man in the game at the moment."
Castleford head coach Danny McGuire issued a withering assessment of his side.
"Ese'ese is a big man but it looks like he's a man against under 10s or something," said McGuire.
"It's just crazy, and it's exactly the same as last week. I just don't understand why he can't be stopped. There's not enough desperation."
The star's muscular display set the tone for a victory that built on last week's gutsy success at Wakefield.
The result tees Hull FC up nicely for next week's Challenge Cup derby against Hull KR, the only team left to separate them from the Super League summit.
Cartwright has the luxury of a long weekend off before the build-up kicks in to next week's derby, and he is relishing the prospect of experiencing the atmosphere of the all-Hull clash for the first time.
"It's exciting - you have to live in Hull to know the feeling in the town at the moment," he said, having been appointed coach after Hull FC managed just three wins in 2024.
"There's a heavy rivalry and I've picked up on that pretty quickly. I'm really looking forward to it, and I think it is going to be a huge occasion."
The only dampener for Cartwright's side was a head knock sustained by Cade Cust in a high tackle by Innes Senior early in the second half, which saw Senior sin-binned and means Cust will miss the Cup quarter-final.
Jack Ashworth's short pass sent Aidan Sezer surging over before halftime, with Sezer's clean kicking helping him rack up a personal tally of 12 points.
with PA
