The visitors took a 2-1 lead with back-to-back strikes shortly before half-time when Joao Cancelo turned home from a Rodrigo assist and Torres scored a golazo from a free kick, redirecting the ball past Newcastle keeper Martin Dubravka with a clever flick.
Newcastle were handed a second penalty right on the hour when Kyle Walker tripped Joe Willock in the box, but the Arsenal loanee saw his spot kick saved only to pounce on the rebound and tuck it into the back of the net.
The goalfest continued and Man City drew level again when Torres reached out to get a foot on a ball into the six-yard box for his second tally of the night.
Torres wasn't done yet, though, as minutes later he completed his hat trick with an acrobatic effort to lash the ball home after Cancelo's curling shot from distance came off Dubravka's far post.
Torres now has 13 goals in all competitions for City this season and while Carson's contribution has been far less, Guardiola was full of praise for his stand-in keeper, too.
"We are incredibly happy for him. He is an important player for us. He is a real leader and today was an exceptional day to let him play," the Spaniard said.
The result saw City's lead at the top of the standings stretch to 13 points while Newcastle are in 16th spot, with Guardiola's team looking ahead to the Champions League final against Chelsea in Portugal on May 29.
Information from Retuers was used in this report.