But long before her stature on the small screen soared, Cilla was an unknown Liverpool lass with an astonishing rags to riches story.
Her early years are about to be relived in a new TV drama charting how Priscilla White was transformed into a chart-topping singing star.
It also chronicles the turbulent highs and lows from tasting fame to finding lasting love.
The three-part offering - simply called Cilla - presents actress Sheridan Smith with the onerous task of portraying the young woman who went on to become a national treasure.
We see her in early 1960s Liverpool, a grim city riven by religious prejudices where prospects were limited. Young people - including Cilla - escaped everyday life by going to see exciting new rock and roll bands at the Cavern Club.
Screenwriter Jeff Pope, who also co-scripted Oscar-nominated film Philomena, says the drama is "a non-patronising look at the working class".
"I thought the earlier part of Cilla's life would be interesting. We live in the X Factor age and I thought it was intriguing to see how Cilla had come up from literally nowhere and how she made it," he adds.
"But at its heart is a love story between Cilla and Bobby - and Cilla and Brian."
The singer's rise in the drama is dominated by two men - Bobby, who went on to be the love of her life and was "very happy to carry the handbag" for such a successful woman, and music mogul Brian Epstein, who plucked Black from obscurity.
He died of an overdose in 1967 aged 34, and a side story of the TV mini-series is his tortured existence as a closeted gay man in the dark days before homosexuality was decriminalised in the year of his death.
West End performer Smith, whose collaboration with Pope on drama Mrs Biggs won her a Bafta, says the drama will bring the two halves of Cilla's career together.
"The younger generation who have got no clue about this and know about Blind Date will get to see this amazing singing career, and the older generation can relive it."
The actress not only had to capture the essence of a youthful Cilla in her portrayal, but had to sing live for scenes from the frenetic buzz of the Cavern Club as 'Swinging Cilla' to the recording studios of Abbey Road.
"In the months leading up to shooting, I had every interview, every piece of footage from the early 60s and there was loads on YouTube so I sat there watching them," explains Smith.
"There's only one Cilla and everyone does an impression of her. I didn't want to do her a disservice and I'm not an impersonator. I wanted to try to get little mannerisms like the way she touched her hair.
"I had some singing lessons - I sing with my mouth wide open, she sings with it quite closed. I know I don't have her voice," she adds, pointing out that Cilla had a "honk" as well as much softer vocals.
The actress recounts how her role led to a dinner date with the star which made the weight of her burden become real.
"I was really star-struck and nervous and I babbled away at her. It's a huge responsibility and you don't want to let them down.
"She gave me her phone number but I was too shy to ring! What do you ask?!" adds Smith. "And I have no plans to make an album of covers - come on, there's only one Cilla!"
But she plays down the performance, saying it was all down to a simple prop synonymous with Cilla.
"I just had to whack my teeth in and I was away! They changed the shape of my mouth so it really helped with the accent."
Pope, whose credits also include Fred West dramatisation Appropriate Adult and The Widower, says Cilla had an important role in creating the drama - and encouraged him to tease out the spikier side of her growth as a star.
The story clearly shows how she could be tough with those around her and was even a match for established artists like songwriter Burt Bacharach.
"She was very insistent that we go into areas that weren't viewed through rose-coloured spectacles. She was very upfront about how determined she was and how sharp her elbows were and had to be in those days.
"Would her tendency be, like her TV shows, to smooth everything out and present a wonderful face to the world? I found the opposite," he says.
"She was in a man's world and I admire her strength," adds Smith.
The writer said watching the films with a figure who remains alive and well was "stressful", not to mention filled with memories.
"Cilla made a joke out of it and said 'this normally happens when someone kicks the bucket.' The emotion of seeing the love of her life [who died in 1999] was massive."
Cilla's story finishes before her marriage to Bobby in 1969 and after the peak of her musical fame. Tellingly, a contract for a BBC television show is found beside the body of Epstein, hinting at the beginnings of a small screen star we all know and love.
Cilla begins on ITV on Monday 15 September at 2100 BST.
Popular entertainer Cilla Black became best known for her huge television hits Blind Date and Surprise Surprise, which dominated the airwaves in the 1980s and 90s.