"It's a partnership that transcends even romance. We're a great, awesome duo."
The gushy encounter led to the stars pairing up for two films that remain rom-com favourites today - 1998's The Wedding Singer and 2005's 50 First Dates.
Now, almost a decade on, the duo reunites in the family comedy Blended, about single parents Jim (Sandler) and Lauren (Barrymore), who, after a disastrous blind date, find themselves stuck with each other - and the five children they have between them - at a South African holiday resort for blended families.
As well as starring in the film, Sandler was also a producer and says as dad to two girls he was drawn to the script for its family themes.
"I really loved the story about good parents wanting to raise a good family and give a nice backbone for their kids to grow up and feel safe," says Sandler, 47.
"I knew we wanted to make a funny movie and I knew we wanted to make a romantic movie but I also just loved the message of, 'If you commit to being a good parent, you've got to be a good parent'."
Despite the time that has passed since Sandler and Barrymore - whose second daughter was born in April - filmed 50 First Dates, Sandler says their goofy chemistry returned the minute they started filming.
"Drew actually said she had a hard time being mean to me in the beginning. I would tell her, 'It's what the movie is - you can do it.'
"But we had fun and Drew was incredible. She played a divorced wife and mother being overwhelmed with, 'How am I going to make my family work?' so well.
"In every scene I couldn't believe how awesome she was and I would always tell [director Frank] Coraci, 'Stay on Drew!'"
The cast also includes Weeds' Kevin Nealon, teen up-and-comer Bella Thorne and Bridesmaids' Wendi McLendon-Covey, who signed on to the film before knowing the story.
"I said yes before I even read the script because I heard it was Adam and Drew," she says.
"So I was like, 'I'll play waitress number four just to be in this.' But when I read it, I was happy to see that blended families are being celebrated because there are a lot of them.
"When you're lucky enough to find love again and you're able to blend the whole family, you should have a fun vacation."
Blended is screening now.