Brodie Halliday, who was dismissed from Regent Night 'n Day Foodstore in September after working there 10 months, told the Employment Relations Authority (ERA) that everyone who worked with him knew "about his weird sense of humour and no-one would take him seriously".
His employer, Lane Group Ltd, said the note on the banoffee pie was just one example out of a string of performance issues, which meant his dismissal was justified.
The note, which was found by a manager read: "I swear to God that if you throw this out I will open my jaw and swallow you like a snake."
Lane Group argued Mr Halliday turned up late, failed to complete many of his assigned duties, loitered on premise after the end of his shift and displayed unprofessional behaviour by using till slips as a scarf and hat during his shifts.
One witness said when customers left Mr Halliday lost focus and would "stare into space".
Mr Halliday says he was was disadvantaged in his employment because he continued to be rostered on to make sandwiches after an incident when he was verbally abused.
He argued the breaches resulted in stress and two periods of sick leave and that Lane Group commenced a course of action that he says was designed to cause him to resign.
The sandwich trainer at the store acknowledged saying "F*** this I’m going home" after becoming fed-up with training Mr Halliday, but denies swearing directly at him.
She said Mr Halliday would not take instruction and would not make the sandwiches the way she asked him to.
When told to follow instructions Mr Halliday would sulk.
Sometimes she said he would sit on the floor which she found quite unusual and sometimes he would cry.
Mr Halliday did not disagree that there were occasions he sat on the floor.
Lane Group argued it was unaware that working in the food room was causing Mr Halliday distress until about June 2016, by which stage he had ceased working in the sandwich room.
In its decision, the ERA ruled Lane Group did not follow its policy over performance issues.
"Some of the reasons for dismissal had not been put to Mr Halliday or put inadequately.
"A decision to dismiss as a result was not one accordingly that a fair and reasonable employer could have reached in all the circumstances."
The ERA said Lane Group did not set out a timetable allowing Mr Halliday to address performance concerns as set out by its own handbook.
"There needed to be some objective measurement.
"In accordance with the policy in the handbook about work performance and rule breaking a fair and reasonable employer could have been expected to have considered a written warning which incorporated all the previous incidents where an explanation was not found to be acceptable."
However, the ERA was not satisfied that Mr Halliday was targeted by his employer.
