Brittany from Dimension Heroes has been stated to fit into this trope, though it has yet to be seen.
Anyone with paranormal powers from Shadow Unit. Merely having paranormal powers doubles a person's calorie requirements, and actually using those powers burns even more calories.
Tennyo, at Whateley Academy in the Whateley Universe. It turns out her mom is a superhero with Energizer powers, and can almost out-eat Tennyo. The one time Tennyo's felt full is after consuming a horde of demons. It's possible her Big Eater habits are an effort to try and make up in quantity for some nutrient that Earth food lacks.
Exemplars and, as mentioned, Energizer type metas are also prone to huge appetites.
The players of JLA Watchtower one time got into a debate of "Which team would win an eating contest? Wally West and Jesse Quick or Gar Logan and Aurora Andersen?" Aurora is about 5'2" and small-built, but is also an animal-shifter like Gar is. Her metabolism resembles a shrew's, especially if she's been working her shapeshifting a lot. Good thing she's also the Team Chef for the Titans.
The guys from Epic Meal Time, who routinely prepare massive dishes with five- (sometimes six-) figure calorie counts and then eat them on camera. What probably helps their frames is that Harley is rather tall and Muscles Glasses (a personal trainer in real life) is often hitting the gym.
Ian and Anthony of Smosh both qualify, although Ian seems to be the bigger eater.
In Survival of the Fittest, Reika Ishida is shown to be one of these in pre-game, judging by the fact that when she orders something from A&W she gets a large hamburger meal alongside some chicken all for herself, and then snags some of the KFC bucket her sister and a friend are sharing. Note that this is a 4'9 tall and 95 pound teenage girl. Jay Holland also shows tendencies of this when he orders six McDoubles that have fries inside them, small cups normally used for condiments to be filled with Oreo McFlurry, four more burgers stacked together, a bunch of milkshakes, a large Pepsi, and coffee at a McDonalds. Though, he does use the justification that he just survived a terrorist attack, so he has the right to get fat.
The SCP Foundation has, among its specimens, SCP-913 AKA "Mr. Hungry", an apparently ordinary African-American man who requires "the recommended daily caloric intake for a normal human every 2 hours", otherwise he falls into a trance in which he will eat any solid matter he can in order to sate his appetite.
In Curveball, whenever Red Shift goes all out, his powers also accelerate his metabolism for the next few days, with a corresponding increase in appetite. In addition, if he's going to be traveling a long distance at high speed, he has to wear a special IV harness that pumps glucose and nutrients directly into his bloodstream (and he's still hungry afterwards).
Steve 1989 MRE Info: Some of the rations Steve features include multiple meals, breakfast, lunch and dinner, all of them high calorie and designed to keep soldiers on their feet and he lets nothing that's edible go to waste.
Strippin jokingly refers to himself as a food disposal unit, and the premise of one of his challenge videos is to face off against Smiffy from Hat Films in a burger eating contest, with the forfeit being that the loser is slapped with a half-eaten burger. Smiffy wins. It is worth nothing that Strippin gets away with this since he is very well-built and does lots of exercise to counteract this.
Turpster, by reputation. Smiffy of Hat Films says that Turps has bought an entire family bucket meal from KFC and eaten all of it, himself. He and Turps have a gentleman's agreement that they will, at some point, do an eating challenge.
Nora in RWBY Chibi can eat a whole cake in one go, and devour stacks of pancakes and still be hungry for more. If she eats too much, she gets a Balloon Belly, but it goes away when she burps. Yang is jealous. It's presumably because she really does have a Hyperactive Metabolism- the warm-up to her workout is enough to leave the others exhausted, so she probably needs to eat so much just to stay on her feet.
Ronove in The Gamer's Alliance eats a lot and always seem to stay hungry no matter how much he has eaten. His favourite foods are strawberry cakes and sand gnome legs.
Menelaos from Greek Ninja. After having caused a row by insulting Japanese food in front of Daichi, later on he is gulping down ramen and enjoying it. When Dawson questions him on it, he replies: "I like it, just I need a lot to get full", as his main grievance was that the portions were too small.
While Mario isn't exactly fat, in The Sonic Amigos he eats all of his and Luigi's spaghetti offscreen. Maybe.
The entirety of the human race in The Jenkinsverse. Humanity's dense bones and efficient muscles and organs mean that a human's dietary requirements are something like quadruple that of most other sapient, spacefaring species of comparable size. Humans abroad in the galaxy are forced to subsist on offensively bland and uninteresting emergency ration spheres in order to meet their basic nutritional needs, and usually at a rate which taxes the supplies of all but the largest ships and space stations.