A guest at Nando's was left disgusted at the lack of cleanliness in the branch's toilets after she discovered a 'mystery' substance covering the seat.
Amanda Jan had been to visit the popular Afro-Portuguese restaurant Blackburn's Peel Leisure and Retail Park on March 21, taking along her daughter, 20, to celebrate Mothers' Day.
Unfortunately, the pair were less then impressed by their visit to the restaurant from start to finish, LancashireLive reports.
Amanda's daughter ordered a grilled chicken wrap and was disappointed with what arrived, noticing that there wasn't much chicken in the wrap at all, and it was mostly lettuce.
The pair didn't want to make a scene at the restaurant, so they wrapped up the meal to take home with them.
Before leaving Amanda went to the toilet, and was left shocked by what she found there.
She says she saw that there wasn't any toilet roll in the cubicles, before noticing that the sink had been left in a horrendous state as a mystery substance covered the entire basin.
The mum said that she was left 'mortified' by the discovery and messaged the restaurant chain about her experience at the restaurant including both the bathroom and her daughter's food.
A reply on March 23 saw Nando's apologised, saying that the food was not at their 'usual standard', as well as giving them a £10 voucher despite the meal costing £43.
Addressing the complaint about the bathroom sink, they claimed that it was just "soap build up" was "missed on our regular toilet checks", though they conceded that it "doesn't look great".
But Amanda was not convinced that it was the result of just one missed check, believing that the toilets are not cleaned regularly.
She said: "The cubicles weren't took bad, but you could tell that they weren't cleaned regularly."
Amanda had noticed that there wasn't any toilet roll, using a scrap piece of paper from the side to wipe the sink thinking that the substance could be rust on the stainless steel, only to realise that it was something else entirely.
She added: "My daughter just wanted to leave.
"I was retching in the car because I had just eaten, I was mortified. I just couldn't help thinking if it's like that, what's the kitchen like?
"That's not just an hourly check that's been missed. If they're not cleaning the bathroom, then surely they're not cleaning the kitchen?"
Amanda's visit to the Nando's was her first in person, as she explained she usually gets takeaway from that particularly branch.
"However, after her recent visit, has vowed never to eat at the restaurant chain again.
Nando's have said that the issue with the sink is due to "ionisation of the concrete basin over time" and is "not due to dirt of mould."
A spokesperson for Nando’s said: “We have robust cleaning procedures in place across all our restaurants and our Blackburn site maintained its five-star Food Hygiene Rating from its latest routine inspection only a couple of weeks ago.
"We are looking into the concerns raised and would like to apologise if we did not meet the high standards we and our customers expect.”