The forward, burying two second-half penalties, has now netted in five consecutive matches at the home of the Baggies and alongside a debut goal for summer signing Timothy Castagne, Brendan Rodgers' side can be satisfied with a brilliant opening to the new campaign.
Story of the Match
Johnstone keeps Baggies level
It took a while for Leicester to really start threatening in the clash but once they did, it was down to Sam Johnstone to deny them. Twice he denied former Baggie Harvey Barnes before the break as he found space in the penalty area.
Foxes' stopper Kasper Schmeichel also had to have his wits about him as Matheus Pereira managed to get in behind the Leicester backline but his shot was deflected away by the Dane's boot.
Castagne breaks the deadlock
It took until ten minutes after the break for the first goal to arrive and having won their last four matches at The Hawthorns, it predictably came Leicester's way. Good play between James Justin and Dennis Praet down the left saw the Belgian break into the box and stand the ball up. The onrushing Castagne then produced a perfect header into the far corner to net his first Foxes' goal.
Rodgers' men thought they had got a second after Ayoze Perez tapped in Barnes' shot that looped up high but the Spaniard was denied by the offside flag.
Vardy cool from the spot
The visitors did eventually double their lead and whilst the opening goalscorer was somewhat of a surprise, the second was almost a certainty. Bursting forwards on the counter-attack, Vardy was hauled down in the box by Kyle Bartley, with the referee pointing to the spot. It was indeed the forward who stepped up and coolly converted to continue his hot streak at The Hawthorns.
He then got another great chance to add to his highly impressive record as a rash challenge from Dara O'Shea saw Justin tumble in the area. It was the same man to take the responsibility and indeed the same result, Vardy adding a second to his tally and a third to a great afternoon's work across the Midlands for Leicester.
Castagne not Chilwell's replacement?
With Ben Chilwell departing Leicester City for Chelsea this summer, it was widely expected that the club would reinvest that money into a replacement. Initially, it looked like Timothy Castagne, arriving from Serie A outfit Atalanta, would be that man. However, the Belgian international played on the right at The Hawthorns, with James Justin moving over to the left.
Whether that is an idea ahead of the return of first-choice right-back Ricardo Pereira, or that there is an arrival at left-back in the works remains to be seen.
Water is wet, Vardy scores at The Hawthorns
If there was one man who the hosts needed to keep an eye on, it was certainly Jamie Vardy. The Foxes' frontman had scored on his last four appearances at The Hawthorns and extended that record even further with two goals from the penalty spot. Thanks to that brace, he now has more Premier League goals than Chelsea hero Didier Drogba.
Step up for West Brom
Traditionally, the pace difference between the Premier League and the Championship is considerable and West Brom will certainly need to learn that if they are to survive. The Baggies for the vast majority were okay but mistakes cost them. Slaven Bilic's men struggled to deal with Leicester in key moments and that was incapsulated by O'Shea's foul for the visitors' second penalty, thinking he had more time on the ball than he did.
It could be a long season for the Baggies if they don't get up to scratch sooner rather than later.