Well, it helps that unless you’re dealing with a really small restaurant (and therefore not many tables) a chef is not working alone. In a lot of restaurants employing a large staff (and therefore the ones with many tables) you’ll find something like a [French Brigade System](https://en.wikipedia.org/wiki/Brigade_de_cuisine) operating.
In a system like this, there are many people in the kitchen each with their own roles and responsibilities. The Chef de Cuisine (literally “Chief of the Kitchen” though also called the Kitchen Chef) is who you are probably thinking of. They are the shot caller, the one who’s name and reputation are at stake. However, they are rarely the ones actually doing the cooking. Their job is to manage the staff, and run the business of the kitchen.
So getting to your question – The reason they can manage it is because they have someone (sometimes the Chef de Cuisine, sometimes a Sous-Chef, and there is a role called the Aboyeur) whose job it is to manage that. That person is not necessarily cooking, but instead managing the orders and ensuring that each plate and order is going out on time, looking correct and tasting as intended.
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