The home side dominated the first half with Staggies goalkeeper Mark Brown forced into several saves, although former Celtic man Rocco Quinn and Alex Cooper both missed great opportunities for the visitors.
However, when Celtic skipper Scott Brown struck a minute after the interval the Highlanders' resistance was broken, and Hooper helped himself to two classic poacher's goals before substitute James Forrest capped his return to action after being out since October with a hamstring injury by grabbing the fourth.
The Scottish champions were drawn against Italian giants Juventus in the last-16 of the Champions League on Thursday, but the exciting prospect of those games to be played in February and March did not spill over into this pre-Christmas fixture, especially in the first 45 minutes when a half-filled Celtic Park was subdued.
However, manager Neil Lennon will have been happier with his side's ruthlessness in the second period as they moved five points ahead of Inverness at the top of the table. And there was the bonus of seeing Forrest back in action.
Lennon was forced into two changes to his starting XI.
Left-back Emilio Izaguirre and striker Lassad Nouioui came in for Adam Matthews and Mikael Lustig, who had succumbed to ankle and hip complaints respectively.
The visitors also showed two changes with Mihael Kovacevic and Quinn in for Ross Tokely and Mark Fotheringham, the former starting on the bench.
County took a point from the champions early in the season in Dingwall, but travelled south without a win in their last eight games and it looked ominous when the Hoops took only three minutes to create their first opening.
Izaguirre raced down the left and his cross found Lassad at the back post, but his header was held by Caley's former Celtic keeper Brown, who made a decent save from Charlie Mulgrew's shot on the turn from a Georgios Samaras free-kick moments later.
Brown looked to be in for a long afternoon and, in the 11th minute, he made a good save from Hooper's close-range header after another Izaguirre cross from the left found the Englishman unmarked in the box.
The visitors lacked conviction when they did venture up the park, although five minutes later former Parkhead midfielder Quinn blazed a drive from 25 yards just over the bar, after being played in by Iain Vigurs.
Celtic's early urgency subsided a little, but they still had County tightly in their grip.
On the half-hour mark Brown was again called into action to save a decent effort from Lassad before another Parkhead attack was thwarted when Hooper's drive came off the face of Marc Fitzpatrick for a corner, which came to nothing.
As Celtic continued to press, midfielder Beram Kayal had a low drive from the edge of the box saved by Brown before the Highlanders broke with some purpose seconds later with Cooper setting up Quinn, but his hastily-taken shot was too tame to unduly bother Hoops keeper Fraser Forster.
Seconds from the break, with the Hoops defence static, Quinn set up Cooper, but England call-up Forster came to Celtic's rescue with a fine blocking save for a corner, which prevented the visitors taking an unlikely lead into the interval.
Any chance of a County upset, however, dissipated just over a minute into the second-half when Hooper set up Brown to drive low past his namesake in the County goal from 14 yards.
With the pressure off, Celtic relaxed and when Hooper flicked Lassad's cross past Brown with his head in the 53rd minute the points were effectively secured.
Forrest was given a rousing cheer when he replaced Kayal, but it was Hooper who had the fans off their seats again in the 64th minute when he was in the right place to head past Brown after Victor Wanyama's header from a Mulgrew corner was blocked up into the air.
It became a matter of how many Celtic would score and, six minutes later, Forrest sped into the County box after taking a pass from Hooper and shot past the helpless Brown.
Lennon was afforded the luxury of giving 18-year-old attacking midfielder John Herron his debut as replacement for Samaras, before Hooper hit the bar from close-range when it looked odds-on he would secure his hat-trick.
- Sports & Recreation
- Rocco Quinn