Two tries to back-rower Jeremiah Nanai, the latter coming from a flying kick retrieval effort over star Panthers Brian To'o and Dylan Edwards, proved the difference for the Cowboys who ended their three-game losing run.
But it would be 33-year-old Taumalolo who ended Saturday's home game the toast of Townsville, swamped by teammates following his first milestone game victory.
With Tonga's king and prime minister watching amid a big crowd, the blockbusting Tonga international turned back the clock with a massive 155 run metres, including one bruising run that resulted in a head injury assessment for Penrith counterpart Isaiah Papali'i.
Cowboys captain Reuben Cotter praised his team's dedication to Taumalolo's milestone as a big contributing factor in snapping their three-game losing run.
"The whole group showed a high level of care for the occasion," Cotter said.
"The club hasn't won a milestone game in so long.
"(Taumalolo) has done so much for this club. He's been here since before I debuted in first grade and what he does out on the field, I've looked up to my whole career.
"I'm very grateful to play alongside him and that we could ice it for him."
The Cowboys - who have now recorded the most victories over Penrith since the Panthers' historic run of form commenced in 2021 - set the tone early by forcing a Moses Leota error in the first play of the game.
A minute later, winger Murray Taulagi crossed for the game's first four-pointer in an ominous glimpse into Penrith's immediate future.
A week on from their shock 19-18 loss to the Gold Coast, Penrith looked bound for another defeat north of the border early in the first half after recording an uncharacteristic seven errors.
"We killed ourselves trying to force the ball, and the errors gave us no field position or rhythm," Penrith captain Nathan Cleary said.
"We lacked a hard-edge mentality across the board which you can never afford."
While Penrith turned the tide two minutes before the break - capitalising on a mistake from Taulagi when Tom Jenkins scored his second try to level the ledger at 10-10 - errors and ill-discipline continued to mar their performance throughout the second half.
Two costly penalties gifted the Cowboys back the lead following an early Cleary penalty goal, before late tries to Nanai and halfback Jake Clifford confirmed a famous North Queensland victory.
7°C