A 15-year-old girl who died after a severe allergic reaction to a baguette from an airport Pret a Manger said "Daddy, help me" as she struggled to breathe, an inquest has heard.
Natasha Ednan-Laperouse became ill on a flight to Nice on 17 July 2016.
Despite her father administering two EpiPen injections, Natasha died in a hospital in Nice within hours, West London Coroner's Court heard.
Pret a Manger said it was "deeply saddened" by her death.
Natasha from Fulham, west London, ate an artichoke, olive and tapenade baguette bought from a Pret shop at about 07:00 BST in Terminal 5 at Heathrow Airport, the inquest heard.
She began to feel ill about 20 minutes into the British Airways flight, and suffered a cardiac arrest and died later the same day.
The inquest heard the baguette contained sesame - which Natasha was allergic to - but the ingredient was not listed on the packaging.
The family's lawyer, Jeremy Hyam QC, became emotional as he read a statement by Natasha's father, Nadim Ednan-Laperouse, at the first day of the inquest on Monday.
Natasha had just finished school for the summer and was on her way to Nice for a four-day "special treat" with her best friend, Bethany, and her father.
Mr Ednan-Laperouse's statement said he first applied an EpiPen when Natasha felt her throat growing itchy and red hives appeared on her midriff.
When her symptoms did not improve he then used her second EpiPen, the inquest heard.
'Agony' of call
"Natasha said that she still couldn't breathe and desperately looked at me, she said 'Daddy, help me, I can't breathe'," the statement read.
She soon lost consciousness and cabin staff and an onboard junior doctor applied CPR for the rest of the journey.
Mr Ednan-Laperouse recalled being "totally focused on saving her life" and "begging her to fight and live", but as his hope began to fade that she would survive in hospital he put a phone to her ear so that her mother and brother could say goodbye, the inquest was told.
"The pain and agony of the call was beyond anything I have known," his statement said.
Mr Ednan-Laperouse told the hearing he had bought the baguette as it "contained all the ingredients she loved and could eat" and the label gave "no indication or mention that sesame seeds were present".
After his daughter's death, Mr Ednan-Laperouse - the founder of Wow Toys company - said he called his own mother and asked her to visit a branch of Pret a Manger in west London to examine a similar baguette.
Finding no ingredients on the label or on the shelf, his mother made inquiries at the counter and was handed a folder of information.
"My mother looked down the list and found that the baguette dough had sesame seed inside it," his statement said.
"I was stunned that a big food company like Pret could mislabel a sandwich and this could cause my daughter to die."
Oliver Campbell QC, representing the chain, said Natasha's father "must unfortunately be mistaken" about his recollections of the packaging, because Pret food does not typically display ingredients.
The inquest heard that Pret fridges usually had transparent stickers with white text outlining allergy information.
Mr Hyam suggested these had not been in place at the airport branch in July 2016.
Abdoulaye-Djouma Diallo, the general manager of the branch at the time, told the inquest he was "confident and sure" he had put stickers on the tills and fridges.
However, Mr Hyam said a health officer from Hillingdon Council visited the branch in May 2017 and reported "there were no till stickers to be seen at the till area".
What are the laws on allergens in food products?
- Sesame is one of 14 allergens that consumers must be made aware of when it is used as an ingredient in food products, according to EU Regulations
- However, the EU rules say individual member states are responsible for deciding on how information about non pre-packaged food is provided to the customer
- The UK's Food Regulations 2014 allow freshly handmade, non pre-packaged food to not be individually labelled
- Pret confirmed at the time of Natasha's death products would not have been individually labelled with allergen or ingredient information, and that this was within regulations
- However, Pret said there were signs in the fridge and at till points telling consumers with allergies to speak to a manager for advice or to see its allergen guide
Natasha had suffered from food allergies her entire life, but diligently scrutinised labels and was alert to the danger of cross-contamination, the inquest heard.
She put "her trust in food labelling", her father's statement added.
Antihistamines, EpiPens and inhalers had never before failed to halt an allergic reaction, he said.
In a statement ahead of Monday's hearing, Natasha's parents said she loved horse-riding, ice-skating, and wanted to pursue a career in law.
They added that she had been "so excited" about what was going to be "her best summer ever".
Representatives from Pret a Manger and BA are expected to give evidence at the inquest, the family's lawyer has said.
The inquest is expected to last five days.