The Lionesses only had a Georgia Stanway penalty to show for their efforts in the first half, as the South Korea defence largely held firm, but Chloe Kelly, Alessia Russo and Lauren James all made the net ripple after the break.
Despite a few fleeting signs of promise from South Korea in the early exchanges, with Cho So-hyun's curling effort landing gratefully in the arms of Mary Earps in the fifth minute, it was one-way traffic forthwith.
James and Ella Toone both stung the palms of South Korea goalkeeper Kim Jung-mi within the opening 15 minutes, with the latter combining well with Stanway and Kelly before seeing her first-time effort saved at the near post.
The well-organised low block of South Korea was proving effective as the hosts dominated possession while huffing and puffing for the opening goal, which very nearly arrived in the 38th minute as Russo struck the inside of the post.
However, only one minute later, the effervescent James burst into the box before being felled by Lim Seon-joo, and referee Andreza de Siqueira did not hesitate to point to the penalty spot.
Stanway stepped up and made no mistake - firing an unstoppable penalty into the side of the net. Jung-mi dived the right way, but her efforts to thwart the Bayern Munich midfielder proved futile.
There was no shred of complacency from the Lionesses following Stanway's opener as Sarina Wiegman's side pressed for a second, but their plentiful periods of possession only counted for a one-goal lead at the break.
The Euro 2022 champions would only need a mere 16 seconds to double their advantage early in the second half, though, as Kelly found her shooting boots but was aided by a significant stroke of luck.
The Manchester City attacker drove towards the edge of the box from the left-hand side before unleashing a shot which looped over Jung-mi following a hefty deflection, as South Korea's defensive solidity was quickly shattered.
With 50 minutes on the clock, Russo got in on the act - taking up a smart position at the near post and flicking the ball over Jung-mi following intelligent play from Alex Greenwood on the left.
It was damage limitation for Colin Bell's team at this point, but they were nearly caught out by a smart corner routine from England in the 63rd minute, as Stanway was left in acres of space to let fly from just inside the box, seeing her effort rattle the crossbar after the slightest of touches from Jung-mi.
While a spate of substitutions from Wiegman did disrupt England's'momentum a tad, there would be time for James to cap off a magnificent debut with a goal in the 78th minute, as the ball fell kindly for her in the area to lash home her first for the Lionesses.
England's attacking incisiveness was on show throughout the evening, but a horror miss came the way of Katie Robinson in the 89th minute, as the 20-year-old crashed a close-range effort against the post after Jung-mi spilled the ball in a dangerous area.
Having immediately surged to the top of the group, next up for Wiegman's side is a meeting with Italy - who lost to Belgium 2-1 in their opening encounter - on Sunday at the Coventry Building Society Arena.