Goals from Mackenzie Smith, Connie Scofield and Aileen Whelan secured three points in the Foxes' opening Group B fixture, with all three finding the net for the first time in a Leicester shirt.
Manager Lydia Bedford shuffled the pack, making eight changes to the XI that narrowly lost to Everton three days earlier in the Barclays Women's Super League. Only Kirstie Levell, Ashleigh Plumptre and Sophie Howard, who captained the side, remained from Thursday.
Full debuts were handed to Demi Vance, CJ Bott and Connie Scofield, while youngsters Monique Robinson, Ava Baker and Smith made their first starts of the season.
Shaping up in a 4-3-3 system, Missy Goodwin and Baker provided width for striker Natasha Flint, who had a hand in breaking the deadlock inside six minutes.
Driving at the defence, the forward cut the ball back from the byline for Smith to convert with a first-time finish, scoring her first senior goal in the process.
Leicester dominated possession while searching for a second and when the ball fell to Bott 25 yards out, her left-footed effort curled wide of the target, unable to trouble Shanell Salgado in the Rovers goal.
Full-back Vance was the next to take aim, from a tight angle on the left, but could only fire over the top of the crossbar. Robinson then headed wide from Goodwin's corner, after Smith's effort was diverted into the side netting by Nicola Worthington.
Blackburn's best first-half chance fell to Farah Crompton five minutes before the break, as she used her pace to break away from City's defence but could not find the finish to match, sending the ball well wide of the far post.
The majority of the play was in the final third at the other end, though Goodwin's attempt to curl a strike over Salgado was unsuccessful, taking a deflection off Chloe Dixon which sent the strike into the 'keeper's arms.
The Foxes fashioned a chance within the opening minute of the second half, with Flint firing wide, and it did not take long for the away side to double their advantage. Goodwin slid the ball across the box for Scofield to side-foot into the roof of the net.
The midfielder looked to turn provider on her maiden Leicester start, setting up Flint, before Jade Richards prevented the forward adding her name to the scoresheet.
City still had to be wary of Rovers on the counter and when substitute Megan Hornby broke from a Leicester corner, she was disappointed not to test Levell, while Goodwin forced a save from Salgado at the opposite end.
Four changes were made on the hour-mark and the third goal arrived on 65 minutes when two of those coming off the bench made a quick impact. Shannon O’Brien applied pressure, allowing Whelan to intercept a back pass, slotting the ball into the near corner.
Another substitute came close to adding a third, though Molly Pike's powerful, first-time strike did not have enough dip to test Salgado.
A debutant was introduced with 20 minutes to play, as summer signing Ellen Jones came on for her first minutes in a Leicester shirt, shortly before Flint took the ball onto her left, curling a shot wide, quickly followed by Vance striking wide from distance.
There was still work to be done to preserve a first clean sheet of the campaign and Levell thwarted Crompton with a diving save, ahead of Natasha Fenton's driven free-kick being kept out by the visiting shot-stopper.
Further opportunities to increase the goal tally came and went in the closing stages. Flint's long-range effort was palmed away, but Goodwin was unable to finish the rebound. Bott's strike was then collected by Rovers' 'keeper, but it was City claiming all three points.
Major moment…
The opener in Lancashire, coming inside six minutes, was a confidence boost for the much-changed Foxes, allowing them to control proceedings from there on in and add two further goals in the second half.
Who impressed?
It was a solid team performance from the 16 players who featured across the 90 minutes, keeping a clean sheet at one end and converting three chances at the other.
Where do we stand?
City top the Group B table on goal difference from Liverpool, who also claimed victory on matchday one by beating Sunderland 1-0. Leicester meet the Reds in their next League Cup fixture, at Pirelli Stadium, on Wednesday 26 October (7pm kick-off).
Coming up...
Next up in the Women's Super League after the international break, LCFC Women visit Manchester City at Academy Stadium on Sunday 16 October (2pm kick-off).
The details…
City: Levell; Bott, Howard (c) (Tierney 60'), Plumptre, Vance; Smith (Whelan 60'), Robinson (Pike 60'), Scofield (E. Jones 70'); Baker (O'Brien 60'), Flint, Goodwin.
Subs not used: Poor, Simon, Purfield.
Goals: Smith 6', Scofield 48', Whelan 65'.
All times BST.
Photo Credit: Blackburn Rovers Ladies.