It was a perfect start for Everton in their opening Group A clash, and the fact that Tim Cahill was playing his first competitive game for the club since March was a welcome boost for the Toffees.
Cahill headed Everton in front when he met a ledt wing Leon Osman cross.
The hosts went two up when Leighton Baines and Steven Pienaar combined well down the left to set up Osman, who fired home a superb second.
Brazilian Silva Cleyton halved the arrears when he took advantage of Joleon Lescott's error to put Larissa back in it, but Victor Anichebe settled matters with a good run and crisp finish.
That late Anichebe goal calmed Everton fans as Larisa had staged a late rally. But the ultimately comfortable win was set in motion by the returning Cahill's opener - a goal greeted ecstaticall by the home fans.
Cahill was in outstanding form throughout his 65-minutes on the pitch. His contribution underlined how much David Moyes's side have missed his bite, energy and goalscoring prowess in midfield.
He had been missing since breaking a dreaded metatarsal against Sheffield United last season.
It was his 100th appearance for Everton, and he msarked the occasion by diving to head Osman's cross past goalkeeper Stefanos Kotsolis on 14 minutes.
Cahill was working well with Spaniard Mikel Arteta in midfield, and the Australian nearly grabbed a second before half-time with a powerful drive from 30 yards Kotsolis saved well.
James McFadden shot at the keeper when clean through, but Osman made no mistake a few minutes later when Baines launched a raid down the left and crossed for Pienaar who found Osman with a clever back flick. Osman hit the ball unerringly into the net.
Cleyton, who had scored twice against Blacburn in the previous round, produced another well-taken goal after 65 minutes as Lescott hesitated on the edge of the area, taking the ball past Jospeh Yobo nd beating Tim Howard.
The goal signalled a spell of concerted pressure from Larissa, but Anichebe restored the two-goal lead by holding off two challenges and netting from 12 yards.
