Lennon confirmed on Friday that the Scottish champions had rejected an offer, reported to be about £5million, from Norwich for the 24-year-old English striker. Hooper got the Hoops off to a fast start when he slid in an Adam Matthews cross in the second minute for his 19th goal of the season.
Georgios Samaras added a second 10 minutes later but after Jason Holt pulled a goal back in the 68th minute there was a nervy spell for the home side which only ended five minutes from time when Hooper grabbed a third, before substitute Lassad Nouioui completed the scoring.
Before the game started there was a minute's applause in memory of Sean Fallon, the former Celtic player and assistant manager, who died on Friday, aged 90.
The home fans were still remembering the Parkhead legend when Celtic took the lead. Right-back Matthews raced up the wing and got the break of the ball as he attempted a one-two before driving into the box and squaring for Hooper to slide in from a couple of yards out.
The Tynecastle side looked all over the place and there was no surprise when Celtic doubled their lead 10 minutes later. Again, the danger came down the Jambos' left-hand side. Midfielder Kris Commons pushed his way past Kevin McHattie and turned Danny Wilson before his shot was parried by keeper Jamie MacDonald out to Samaras who tapped into an empty net.
Hooper then forced his way past the Hearts defence only to be thwarted by MacDonald with Joe Ledley's shot from the rebound blocked by Andy Webster.
Jamie Walker replaced Callum Paterson for the start of the second half and within five minutes he had tested Lukasz Zaluska with a low drive after skipping through the Celtic defence. Seconds later Hooper had the ball in the net from a Commons cross but was ruled offside.
The visitors found themselves back in the game when Holt burst through the middle and unleashed a drive which deflected off Mikael Lustig and spun past Zaluska.
A game that had been a stroll for the home side took on an edge but in the 85th minute, following determined work by Scott Brown, the ball fell to Hooper and he slammed it low past MacDonald. Lassad made it four as the game nudged into added time when he converted a cross from Emilio Izaguirre.