Dame Vera turned 100 on March 20 and marked the occasion by releasing a new album.
They also serenaded her with a selection of her best-loved hits including We'll Meet Again and The White Cliffs of Dover.
Her image on the cliffside was commissioned to mark her centenary and the release of her new album, Vera Lynn 100, which features re-orchestrated versions of her most beloved music alongside her original vocals.
Older patients being cared for at Basildon University Hospital raised a teacup in honour of Dame Vera Lynn, who was known as the forces' sweetheart during the Second World War.
To celebrate the landmark birthday, Dame Vera's image was projected on to the cliffs, as she officially became a centenarian.
She told the Press Association: "Dame Vera, we've met a lot of times over microphones".
The white cliffs of Dover, which she sang about in the eponymous song, were lit up with a 350ft projection of the singer's face, along with the words "Happy Birthday Dame Vera Lynn" and "Celebrating 100 years of a national treasure".
She began performing at the age of seven and gave up school aged 11 to start touring.
The care home, joined by friends and family on March 20, celebrated the milestone birthday of "The Forces Sweetheart". with a slice of birthday cake and a tuneful rendition of Vera's popular war-time song "We'll Meet Again".
Having never had professional musical training, viewers will learn how the early days of her career saw Lynn spend "hours leafing through sheet music" in London's Denmark Street to find the songs she wanted to perform.
The White Cliffs of Dover are set to receive a temporary makeover in honour of Dame Vera Lynn.
"It is an unprecedented honour to have my birthday marked in such a attractive way and I am truly thrilled by this wonderful gesture", she said, according to The Telegraph.
"I always looked at the lyrics first because I thought they were more important and, if I liked them, then I would look at the tune", she says.
Lynn was also known for her charity work.