The fact that Amy's Baking Company managed to be so unhinged that a single episode has its own subsection on the series' main page. It takes a lot to stand out amongst 12 seasons' worth of shows produced in two different countries.
The quote on the top of the main page comes from the American episode "Sebastian's", where the owner was a complete egomaniacal nutcase who pretty much tried to actively sabotage Ramsay's efforts to improve his restaurant, hurting not just the business but the staff as well. After Sebastian tries to push his "concept" one final time, Ramsay pulls him aside and calmly tells him that. After watching this guy act like a massive Jerk Ass the whole episode, seeing Ramsay put that schmuck in his place is immensely satisfying.
In that same episode, Sebastian is crowing that "I just won that one!" after Ramsay walks out on an argument to clear his head. Upon returning, Ramsay announces, "You have won jack fucking shit!"
In the Spin-A-Yarn Steakhouse episode, the owner, Saki, has his wife serve the restaurant's new signature prime rib tableside as part of an effort to involve her more in the business. Being new to the task, she cuts enormous portions, practically giving away the meat. After an entire sports team arrive and all unanimously choose to order the steak, the owner, wife and Ramsay find out that (to their horror) there are only about 2 pounds of Rib left, certainly not enough to serve an entire team. Cue Victor, the head chef (who earlier in the episode was reduced to washing dishes during dinner service because of the lack of help), mentioning that he prepared one last rib roast just in case something went wrong.
It's not made entirely clear to the viewer just why this is so crucial. Prime rib is different than some other steaks because it takes much longer to prepare properly. First, it (i) sits at room temperature for about two hours, then (ii) spends another two hours in the oven at varying temperatures. Without the "emergency" prime rib, it would have been literally impossible to fill the order and no amount of chef wizardry could have done anything about it.
In the Park's Edge episode, one of the line cooks has voiced opposition to including chicken wings on the new menu, and begins to intentionally screw up orders during the relaunch night. The head chef, who had no previous experience outside of cooking school, tells him to stop complaining and just cook the food properly. When the line cook mouths off again, the head chef fires him on the spot in the middle of dinner service.
In the Blackberry's episode, the owner/head chef walks off the line in the middle of the relaunch after being called out for interfering with the other chefs and reverting to her old ways, which included meddling in dishes that others were cooking. The sous chef, with some encouragement from Gordon, steps up and gets every dish served properly once she leaves.
Another in that episode is basically anytime that Mama Mary opens her mouth: First, she tells her daughter to shut up, ditch her arrogance, and accept the help that Gordon is offering, and the second is when she confronts her daughter for walking out of the dinner service, telling her that if she is going to behave like this, she should just close the restaurant down. Not to mention her red velvet cake was the only food Ramsay liked during his sample meal.
Gordon catching and confronting the guy who's stealing food and booze from the kitchen (named, appropriately enough, Buzzard) and getting him fired is at once badass, awesome, and quite brave too. Gordon instantly bursts the guy's bubble as soon as he comes swaggering into the kitchen wearing a pair of Cool Shades and then tells him what he would do in the situation:
Can I see your eyes, can you take your glasses off?
I just have one discipline, anyone who steals from me is out. End of story.
Gordon's utter shredding of the owners of "Burger Kitchen", who insisted upon almost force-feeding him their gimmicky Wagyu burgers (which, incidentally, he routinely mispronounces as "way-goo", further making it clear he doesn't have a clue what he's talking about), to the point of getting in the way of David's, their (former) head chef, attempt at showing Ramsay his own burger recipe that the owners were refusing to implement. Even better, Ramsay declared David's "Redemption Burger" to be absolutely delicious.
Ramsay bringing in all the people who wrote the bad reviews on the restaurant was also epic, showing how yes, they're real people, not trolls or spokesmen for the competition.
Gordon's "The Reason You Suck" Speech towards Amy and Samy and their business, Amy's Baking Company. They simply refuse to listen to him and repeatedly try to play the victim card; he finally just outright tells them he can't help them and leaves.
Ramsay during that entire episode was awesome, calling the owners out multiple times on their bullshit and twice telling customers what was wrong with the place. He also stuck up for the abused waitresses, telling the customers that they were getting their rightfully deserved tips stolen. Given the managers' behavior, he acted very calm and mature and was a much bigger person than they were. Any other person would have given up on them a long time ago.
That last bit is even more awesome considering that this is ChefRamsay we're talking about! He only had one loud outburst throughout the entire episode and was pretty much calm, cool, collected, and polite the rest of the time.
This exchange between Gordon and Joe, owner/chef of the Mill Street Bistro.
Gordon: Defensive, ignorant, and in complete denial...
That whole episode was amazing. When Joe decides to put raw onions in a French Onion Soup and Ramsay goes off on him with such anger and ferocity.
When Joe starts cooking like he used to before Gordon's arrival, Ramsay has finally had enough of his denial and incompetence and kicks Joe out of his own kitchen and throws the latter's crappy elk quesadilla on the floor and rhetorically asks him to take it with him. Joe's exit allows Gordon and sous chef Tom to complete service without much issue.
In the Piccolo Teatro episode of the UK series, Gordon decides to prove that lunch services can be profitable by opening the restaurant for lunch without the owner's knowledge. He ends up prepping, cooking and serving the lunch item (tomato soup with a toasted cheese sandwich) by himself, and ends up making over €500 in profit.
Momma Cherri's Soul Food Shack had a first-and-only moment for the show. Gordon Ramsay liked the food and didn't send it back. He thought the presentation wasn't the best and the restaurant was a little small, but he cleaned his plate; when he brought the empty dish back to the kitchen, he declared the meal to be "bloody delicious."
Cherrita: I fed Gordon Ramsay...and he cleaned his plate!
Ramsay laying the smackdown on chef Damien of Oceana after realizing how poorly the food is being maintained. At one point, Damien - visibly flustered - calls Ramsay an asshole, which only increases his criticism. Eventually, Ramsay manages to somewhat break through to him.
Ramsay: I've got just one question to you; who's the arsehole now, "chef"?!
In the Lido di Manhattan episode, half of the kitchen staff walk out on Gordon and the owner of the restaurant. Gordon quickly saves things by calling in his right hand man Scott and with Scott's help, they save the service and make it a success.
Ramsay also lets everyone take a swing at a computer with an awful POS system that slowed down service all the time.
In the Season 1 episode "Campania", at the beginning of the reboot service, the new food is receiving praise... until one customer complains that her dish is terrible and that she wouldn't feed it to her dog. Usually this means the gradual fall of the service and food quality, with the chef being pressured, right? Well, that does happen, but not there. When the dish is sent back, Ramsay himself inspects it and finds nothing wrong with it. When the woman continues to spout out insults on the food, he promptly tells her to stop talking out of her rear, stop trying to make trouble, and then apologizes to the other customers for the "old hag."
And later, in that same episode, one table waits two hours and receives no food. Now, one customer reasonably gets upset, until she goes to the front of the restaurant and complains to another customer of the food tasting terrible, despite the other customer insisting that it was great. A drunk but satisfied customer comes and tells her to stop complaining if she kept eating her food, only leaving her alone when a police car arrives.
PJ's Steakhouse had a Smug Snake chef named Eric that tries to blow over every complaint his way. Ramsay basically puts him in his place 9 times out of 10.
The fact that Capri is still in business counts. When Gordon arrived, the twin brother owners were immature, inexperienced and would start crying over little things such as being told the food was rotten. By the end of the episode, he's forced them to grow up in a short span of three days and the lesson clearly held.
In a rare case of an awesome "Reason You Suck" Speech being delivered by someone other than Gordon Ramsay; in the Runaway Girl episode, the beleaguered head chef who is also the long-time best friend of the restaurant owner calls him out on all of his bullshit and unloads years of pent up rage in an explosive rant that leaves even Gordon himself utterly slack-jawed and speechless as he steps out.
The Mama Maria's episode deserves some mention due to the fact John is one of the few owners of Kitchen Nightmares who does change for the better and keeps his restaurant afloat, finally becoming the owner he has to be. Also adds a moment of Heartwarming as he's finally able to move on from his parent's passing.
In the "Greek at the Harbor" episode, Aris, the owner's son, holds a table between his teeth.Even Gordon is impressed. Then, he acknowledges a dish that was sent back was "dry as hell" when he can't even cook. Pretty amazing for a son that was trying to redeem himself after publicly declaring he didn't want to inherit the business.