An Adelaide baker to the stars has recalled her encounter with a dishevelled, seemingly “delusional” man who turned out to be legendary heavy metal rocker Ozzy Osbourne, who has now died at aged 76.

Sugar and Spice Cakes owner Amanda Forth-Piper said the 1998 brush with fame was a lesson in “not judging a book by its cover”.

She recalled the incident after news broke of the death of Osbourne, the former Black Sabbath singer-turned-solo act known as the Prince of Darkness. His wife, TV personality Sharon Osbourne, had revealed in February that he had Parkinson’s disease.

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Forth-Piper said she feared she was about to be robbed when the rather dishevelled man walked into her bakery at Millswood, in Adelaide’s inner southern suburbs, and asked for a cake for his wife.

“I honestly didn’t think it was anyone famous,” Forth-Piper told www.20304050.best

“I thought that I was genuinely being held up.”

Forth-Piper said she listened to the man’s request, thinking he had strayed in her shop by accident and did not actually want to purchase a cake.

“So, as this story is unfolding, I’m thinking, this is, this guy is just delusional,” Forth-Piper said.

“He’s making all of this up.

“But I took all of the details and I didn’t take any money, but he did have his wallet and when I saw it was filled with American $100 bills I started to think maybe this guy is serious.”

The man described the cake he wanted made for his wife, Sharon, and asked for it to be delivered to “Ozzy” at Thebarton Theatre that evening.

As soon as he left Forth-Piper immediately rang her dad to see if he knew of a singer named Ozzy.

“I rang my dad straight away and said, ‘Is there a guy called Ozzy having a concert tonight at Thebarton Theatre?’,” she said.

“He was like, ‘Absolutely, and his wife’s name is Sharon — that is Ozzy Osbourne you were just dealing with’.”

Ozzy had ordered a delicious mixed berry chocolate mud chocolate which “had to have black and white on it, and it had to have red roses,” Forth-Piper said.

Ozzy is not the only celebrity Forth-Piper has baked for during her 29 years in business, with other music and Hollywood royalty customers including TV host Oprah Winfrey, and singers Beyonce and Pink — who also came in person to order a birthday cake for a loved one.

“When the celebrities come to town, we get the call up, like Jennifer Lopez, it was her twin’s birthday when she had a concert here,” Forth-Piper said.

“Same as Pink, it was her daughter Willow’s birthday. Beyonce, it was her daughter’s. birthday.”