A teenage waitress was left embarrassed and ashamed after a customer mocked her for being Māori.

Mia Griffiths, 17, works part-time at a popular restaurant in the Auckland Viaduct.

During a busy evening shift on Monday, she served a table of employees from building materials company James Hardie, who were attending a senior leadership team dinner.

Mia says one man at the table was a difficult customer who complained about the set menu multiple times. When she set down a platter of Kaipara lamb shoulders, his comments took on a racist tone.

"He looked me up and down and said, 'I bet your whānau doesn't come here often, they're at home eating boil-up'."

She felt he was implying that because her family is Māori, they couldn't afford to eat at a Viaduct restaurant. Mia told Newshub her parents eat there reasonably often.

"I didn't know how to reply because I was so ashamed. I was standing there in absolute embarrassment and shock. I just couldn't believe what I heard."

She says the man repeatedly used the word 'whānau', mockingly pronouncing it 'faarnow'.

None of the other customers at the table - most of whom were white, she says - challenged the man on his remarks, and most of them seemed amused.

"This guy kept looking at the other people for validation, and they kept laughing like they were watching an animal at the circus… the whole table was laughing at me."

She finished serving the food and returned to the kitchen, where she burst into tears.

The bartender told her he'd seen what had happened, and the head waitress gave her permission to take a break and compose herself. But soon she had to return to the table, which kept ordering more food and was "difficult to maintain".

"I just had to continue serving because I'm better than that. I tried to push it to the side."

She was afraid to say anything to the man for fear of losing her job. She was also mindful that August is Restaurant Month, and didn't want to jeopardise any reviews for the establishment, which is relatively new and owned by her friend's parents.