Zigzagged with Jelly, Paul Vitti's right-hand man in Analyze This. He is fat (likely how he got his name), he is a mobster (and he has killed a few people in his career), but he's more of a Noble Demon.
Just in case anyone missed it in the opening paragraphs, Fat Bastard from the Austin Powers films is the Trope Namer. He is an ill-tempered Scot who weighs a metric ton and Eats Babies. Though the end of his debut movie does try to paint him in a sympathetic light for about a minute or two...and then he blows it by farting at the end of his heartfelt monologue, and decides to kill Austin and his Love Interest anyway.
By the time of his return in the sequel, he's taken his "bastardly" ways into Sumo Wrestling as a way of "going legit" but quickly proves he's still got his mind in the gutter. This is then subverted by the epilogue when it's shown he has mellowed out and shed about 180 pounds thanks to going on the Subway diet "just like Jared", at the cost of having a lot of excess skin and a neck shaped like female genitalia.
Big Fatso, the leader of a Black gang in Barb Wire is so fat that he needs a crawler to move.
Lt. Eckhardt in Batman (1989), who's an Expy of Pre-Crisis Harvey Bullock, a Dirty Cop working for the mob.
Beautiful People (2014): Nibbio, the leader of the thugs, is a thoroughly unpleasant, murderous man. He breaks into peoples' homes with his younger brother Brett, and his friend Testamento, where they proceed to loot the house, force the occupants to fearfully perform whatever action he demands of them, and then kills them.
Blade: Pearl, the morbidly obese blob of a vampire record keeper. The only record keeping he keeps is his mouth! Might have been the basis for Balthazar in Buffy the Vampire Slayer.
Chip 'n Dale: Rescue Rangers (2022): After getting blacklisted by Hollywood, Peter Pan lets himself go and becomes Sweet Pete, who turns toons into bootlegs to sell them to the black market.
The Commitments about an Irish R&B group has lead singer Deco an obnoxious and egomaniacal lout.
Serial killer "Crazy Fat" Ethel Janowski from the Criminally Insane duology.
Detective Hung from Crime Story, a Corrupt Cop and the protagonist's Pointy-Haired Boss who is secretly The Mole working with the triads. In his first scene, Hung is shown forcing his fat, oversized gut on a reluctant call-girl, sexually humiliate her and then slapping her for crying. It gets even worse from there...
Cryptz: The bouncer is a big fat Black guy who works for a strip club that's staffed and run by vampires.
Cross-dressing John Waters star Divine, playing a man, was always unsympathetic and unlikeable. As a woman, at least "she" was the protagonist (extended to non-John Waters movies like Trouble in Mind and Rustlers' Rhapsody).
D-Day has The Dragon, Gelda, an overweight brute who gleefully intimidates Ivan's daughter Zhenya after kidnapping her, and later tries to drown Zhenya to force Ivan to fight him, gloating all the way and enjoying himself a little too much.
Both Herman Goering and Martin Bormann in Downfall (2004) are both fairly wide, and are both unrepentant Nazis who are high-ranking members of Hitler’s inner circle. Special mention goes to Bormann, who manages to make good on his bid to make himself the most powerful man in the Nazi Regime.... which is gonna collapse in a few days, courtesy of the Red Army and the Allies.
Baron Vladimir Harkonnen in Dune (2021) and it's sequel is so overweight he needs an anti-gravity device to move. He's also very evil and the main source of misery for the protagonist Paul.
Dungeons & Dragons: Honor Among Thieves gives us a live-action Themberchaud, an adult red dragon who's so fat he can barely walk (definitely can't fly) and spends most of his on-screen time rolling around killing and eating people, unable even to use his dragon-breath thanks to his size.
First Blood: While not exactly fat and more big boned, Teasle has an imposing physique and described by Rambo to be "king shit".
The Girl with the Dragon Tattoo (2011): Extremely obvious example as Bjurman is thin or at least average build in every other version, but very overweight here, and treated as disgusting even before he violently rapes Lisbeth.
Goebbels and Geduldig: SS Standartenführer Eugen Haase is fat, prone to Kick the Dog and has an inflated opinion of himself if a painting of him as a medieval knight with a steel helmet and swastika armband is any indication.
Harsh Times: The government spook who tries to recruit Jim and his "talents" for his US task force in Colombia is noticeably overweight and sweaty. He also advises Jim to dump the Mexican girl he wants to marry and just get a bunch of Colombian mistresses.
The Great Goblin in the film adaptation of The Hobbit.
Goldfinger: The namesake gold-obsessed and heavyset Big Bad who wants to nuke Fort Knox himself, Auric Goldfinger (Gert Fröbe), as well as his mute Battle Butler and trusted main henchman, Oddjob (Harold Sakata). The latter remains an iconic example of Stout Strength that Bond can't hope to best in a physical fight, resorting to another method to kill him.
Tomorrow Never Dies: Henry Gupta (Ricky Jay), a heavyset Evil Genius techno-terrorist who helps engineer the nefarious plans of the Big Bad, media mogul Elliot Carver.
Jurassic Park: Dennis Nedry is slobby, he's abrasive, he's played by Wayne Knight, and he's a corporate spy who sabotages the whole island (endangering many innocent people) to steal some dinosaur embryos for InGen's rival, BioSyn. He also meets a tremendously Karmic Death, courtesy of a Dilophosaurus.
Midnight Madness: Blue Team leader Harold is a grouchy Big Eater who can barely go ten minutes without cheating.
Mr. Creosote from Monty Python's The Meaning of Life is so fat that he can hardly walk, and is very rude and inconsiderate to the restaurant staff. The worst part is that he continuously vomits on everything, including the floor, the menu, the cleaning lady, and the maître d', while making everyone else's dining experience so unpleasant that there's a Vomit Chain Reaction.
Nobody Sleeps in the Woods Tonight: The twins are a pair of murderous psychopaths due to being the hosts for some black alien sludge that crawled into them when they were kids.
No Escape (1994): The Warden is quite rotund and a ruthless, evil man. King, who's equally large, is The Mole for him inside the Insiders, although it's implied he did this more out of desperation to escape than actual malice.
Rasputia from Norbit starts out as a domineering, abrasive child, and grows up to be a bitter, vindictive, and not exactly petty woman.
Overdrawn at the Memory Bank had "really, REALLY big brother". Can someone please turn off the revolving fat man?
Pathology: The man murdered by Juliette and Ted is only identified in the credits as 'Fat Bastard'. However, given Juliette's story about all of the awful things he did is a lie, how much of a bastard he really is remains unknown.
In The Pit and the Pendulum (1991), the overweight and slovenly Gomez is the assistant to the Torture Technician Mendoza, and also performs many of the menial tasks for the Inquisition, such as carting the bodies out of the castle and dumping them. His Establishing Character Moment is accepting money from Antonio to smuggle him into the castle, and then betraying him to guards as soon as they are inside.
The cruel and corrupt Porky from the Porky's series of movies.
Mathilda's father in The Professional is an abusive and cruel man towards her own daughter as well as being a pervert who would jump at every chance to have sex with his own wife. He's also a handler of drugs for corrupt DEA agent Norman Stansfield and his Dirty Cop crew. It's also implied that Mathilda's stepsister is also obese since we see her trying to lose weight and she's also quite abusive towards her (though she does love her younger brother just like her sister).
The dead-o Pulaski, a.k.a. "Fat Elvis" from R.I.P.D.. Applies to a few others, as well.
Rise of the Scarecrows has two examples. Carlos, one of the main cast, is a rude, disrespectful Jerkass to everyone. Plus, there's that one kid in Pete's first scene who showed him both his middle fingers.
Max (played by Marlon Brando)in The Score. Max is a lisping, money-grubbing, grossly overweight fence who betrays his best thief (and possibly only friend) in an attempt to buy his way out of debt.
Jabba the Hutt of Star Wars fame. Yes, he's an alien, but he is fat, even for Hutt standards. He was originally supposed to just be a fat hairy alien before Lucas's budget got boosted for the two sequels.
A Serbian Film: Vukmir's henchman, Raša, a creep who delightfully partakes in raping an infant and later had no qualms partaking in ruining Milos' life. Fittingly, he suffers the most spectacularly gruesome and ironic death in the whole movie.
The Strange Door: Alain is quite pudgy and is a petty, superficially jovial sadist who casually orders murders and wants to ruin the lives of his brother and niece over a decades-old case of being Not Good with Rejection in a Sibling Triangle.
Jannes the High Priest of Egypt, played by Douglas Dumbrill, and his frustration at Moses's action in taking away his and his priests' temple grain to feed the Hebrew slaves leads to his secretly siding with Moses's rival Rameses.
An even fatter, sneakier, villainous-er character from The Ten Commandments is Dathan, the Hebrew overseer. He does everything Jannes does, but he does it because he loves power, and because the hottie he has his eye on prefers Joshua, the stonecutter with the chiseled (get it?) abs.
In Terror in a Texas Town, the corpulent McNeil seeks to control all the land in the valley, and uses threats, intimidation and violence to drive the farmers off their land.
In The Third Man, Popescu is an Affably Evil overweight enforcer for a local crime lord. He stalks the intrepid Holly Martins throughout a bombed out Vienna, constantly threatening him and siccing thugs, all while wearing a fashionable suit.
Most of the characters played by Laird Cregar, perhaps most memorably the prissy chocoholic villain Willard Gates in This Gun for Hire.
Tickles the Clown: The titular clown is certainly wide in the middle. He's also a thoroughly unpleasant person who's serving a life sentence for an unspecified crime.
Underworld U.S.A.: Connors, the completely amoral gang boss who tells Gela to start targeting schools to sell his dope because they need to improve their bottom line, is noticeably corpulent and is seen eating in many of his scenes.
O'Brien, the local rep for the Southern Oil Company in The Wages of Fear, who happily sends the central characters on what is essentially a suicide mission for little more than the price of a ticket home.
Wesley: She has one single iota of tenuous power! She thinks she can push everyone around. (Grabs Janice's stapler) You don't need this. (Smashes it against the wall against his cubicle, breaking it) I understand. Junior high must've been kind of tough, but it doesn't give you the right to treat your workers like horseshit, Janice. I know we laugh at you, Janice. We all know you keep a stash of jelly donuts in the top drawer of your desk. But I want you to know, if you weren't such a bitch, we'd feel sorry for you. I do feel sorry for you. But as it stands, the way you behave - I feel I can speak for the entire office when I tell you... go fuck yourself.
. Junior high must've been kind of tough, but it doesn't give you the right to treat your workers like horseshit, Janice. I know we laugh at you, Janice. We all know you keep a stash of jelly donuts in the top drawer of your desk. But I want you to know, if you weren't such a bitch, we'd feel sorry for you. I do feel sorry for you. But as it stands, the way you behave - I feel I can speak for the entire office when I tell you... go fuck yourself.