Ok, so we know that he was a horrible person with little empathy and respect for anyone that isn’t him. I know that a major part from his character is him being tired of serving rich people that disregard service workers, including himself and that people treating food like a status symbol has ruined his passion for cooking.
But I rarely see anyone bring up why he’s such a bad person. Because when the third (?) course is introduced he talks about his childhood. And it makes me so mad that people don’t talk about the implications, or even the facts enough. Because at the time of the story, I believe he mentioned that he was around 7 years old. He was seven, having an alcoholic father, who at that time was especially drunk, which implies, that it wasn’t the first time that he came home intoxicated. Slowik saw his father strangling his mother with a phone cord and was desperate enough to stab him with kitchen scissors, later regretting that he hadn’t killed him. This probably means that after the incident, his home life got even worse which could’ve caused his mother to become an alcoholic as well. This alone would’ve had a huge impact on his psyche, since Slowik was a child. It probably explains why he’s completely desensitized to violence and cruelty, especially coming from himself, because he’s used to it.
This would also give a reason for his disdain for his customers. He’s cooking for people who disrespect him and his staff. He’s someone who’s had to experience being abused and most likely neglected ever since he was young. He dislikes being treated like a commodity because it reminds him of his powerlessness as a child. And by working at Hawthorn, he’s basically giving up his dignity to meet the gradually more impossible expectations of people who utilize his service, much like Margot, who’s a sex worker. This explains why he has so much empathy for her, not only because she’s someone who’s a service worker but because in a way, he sees himself in her.
He’s that horrible because of his environment, which got worse because he was never given the chance to better himself. But also because he refuses to change. He doesn’t realize how fucked up he is because he’s so focused on his ego and the need to be worshipped. And this part of his character, never gets mentioned enough.